chore: update tox OTel test deps to 1.40/0.61 and include tox.ini in nightly dependency updates (#693)

*Description of changes:*

Currently builds are running with the following warning:
```
opentelemetry-sdk 1.40.0 requires opentelemetry-api==1.40.0, but you have opentelemetry-api 1.39.1 which is incompatible.
opentelemetry-semantic-conventions 0.61b0 requires opentelemetry-api==1.40.0, but you have opentelemetry-api 1.39.1 which is incompatible.
opentelemetry-test-utils 0.60b1 requires opentelemetry-sdk==1.39.1, but you have opentelemetry-sdk 1.40.0 which is incompatible.
```

Update tox.ini OTel test deps to 1.40/0.61 and auto-update tox repo
branches in nightly builds, validated with the following script:

```
python -c "
from scripts.update_dependencies import update_file_dependencies
import shutil

shutil.copy('tox.ini', '/tmp/tox_test.ini')
result = update_file_dependencies('/tmp/tox_test.ini', '1.41.0', '0.62b0', {})
print(f'Updated: {result}')
with open('/tmp/tox_test.ini') as f:
    for line in f:
        if 'CORE_REPO=' in line or 'CONTRIB_REPO=' in line:
            print(line.strip())


Updated /tmp/tox_test.ini
Updated: True
CORE_REPO=git+https://github.com/open-telemetry/opentelemetry-python.git@release/v1.41.x-0.62bx
CONTRIB_REPO=git+https://github.com/open-telemetry/opentelemetry-python-contrib.git@release/v1.41.x-0.62bx
```

By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice.

Author: liustve

scripts/update_dependencies.py

@@ -78,6 +78,33 @@
 ]
 
 
+def _replace_dep_versions(content, deps, version):
+    """Replace version pins for a list of dependencies in content."""
+    updated = False
+    for dep in deps:
+        pattern = rf'"?{re.escape(dep)}\s*==\s*[^\s,\]"]*"?'
+        replacement = f'"{dep} == {version}"' if '"' in content else f"{dep}=={version}"
+        if re.search(pattern, content):
+            content = re.sub(pattern, replacement, content)
+            updated = True
+    return content, updated
+
+
+def _replace_tox_repo_branches(content, otel_python_version, otel_contrib_version):
+    """Replace tox CORE_REPO/CONTRIB_REPO branch references."""
+    core_match = re.match(r"(\d+\.\d+)", otel_python_version)
+    contrib_match = re.match(r"(\d+\.\d+b?)", otel_contrib_version)
+    if not (core_match and contrib_match):
+        return content, False
+    new_branch = f"release/v{core_match.group(1)}.x-{contrib_match.group(1)}x"
+    pattern = (
+        r"((?:CORE|CONTRIB)_REPO=git\+https://github\.com/open-telemetry/"
+        r"opentelemetry-python(?:-contrib)?\.git@)release/v[\d.]+x-[\d.b]+x"
+    )
+    content, count = re.subn(pattern, rf"\g<1>{new_branch}", content)
+    return content, bool(count)
+
+
 def update_file_dependencies(file_path, otel_python_version, otel_contrib_version, aws_versions):
     """Update all Otel dependencies in a given file"""
     try:
@@ -86,31 +113,19 @@ def update_file_dependencies(file_path, otel_python_version, otel_contrib_versio
 
         updated = False
 
-        # Update opentelemetry-python dependencies
-        for dep in PYTHON_CORE_DEPS:
-            # Handle both "package == version" and package==version formats
-            pattern = rf'"?{re.escape(dep)}\s*==\s*[^\s,\]"]*"?'
-            replacement = f'"{dep} == {otel_python_version}"' if '"' in content else f"{dep}=={otel_python_version}"
-            if re.search(pattern, content):
-                content = re.sub(pattern, replacement, content)
-                updated = True
-
-        # Update opentelemetry-python-contrib dependencies
-        for dep in CONTRIB_DEPS:
-            pattern = rf'"?{re.escape(dep)}\s*==\s*[^\s,\]"]*"?'
-            replacement = f'"{dep} == {otel_contrib_version}"' if '"' in content else f"{dep}=={otel_contrib_version}"
-            if re.search(pattern, content):
-                content = re.sub(pattern, replacement, content)
-                updated = True
-
-        # Update independently versioned AWS dependencies
+        content, changed = _replace_dep_versions(content, PYTHON_CORE_DEPS, otel_python_version)
+        updated = updated or changed
+
+        content, changed = _replace_dep_versions(content, CONTRIB_DEPS, otel_contrib_version)
+        updated = updated or changed
+
         for dep, version in aws_versions.items():
             if version:
-                pattern = rf'"?{re.escape(dep)}\s*==\s*[^\s,\]"]*"?'
-                replacement = f'"{dep} == {version}"' if '"' in content else f"{dep}=={version}"
-                if re.search(pattern, content):
-                    content = re.sub(pattern, replacement, content)
-                    updated = True
+                content, changed = _replace_dep_versions(content, [dep], version)
+                updated = updated or changed
+
+        content, changed = _replace_tox_repo_branches(content, otel_python_version, otel_contrib_version)
+        updated = updated or changed
 
         if updated:
             with open(file_path, "w", encoding="utf-8") as output_file:
@@ -149,6 +164,7 @@ def main():
         "contract-tests/images/mock-collector/requirements.txt",
         "contract-tests/tests/pyproject.toml",
         "lambda-layer/src/tests/requirements.txt",
+        "tox.ini",
     ]
 
     any_updated = False

tox.ini

@@ -27,9 +27,8 @@ deps =
   3.{10,11,12,13}-test-aws-opentelemetry-distro: uvicorn
 
 setenv =
-  ; TODO: The two repos branches need manual updated over time, need to figure out a more sustainable solution.
-  CORE_REPO=git+https://github.com/open-telemetry/opentelemetry-python.git@release/v1.39.x-0.60bx
-  CONTRIB_REPO=git+https://github.com/open-telemetry/opentelemetry-python-contrib.git@release/v1.39.x-0.60bx
+  CORE_REPO=git+https://github.com/open-telemetry/opentelemetry-python.git@release/v1.40.x-0.61bx
+  CONTRIB_REPO=git+https://github.com/open-telemetry/opentelemetry-python-contrib.git@release/v1.40.x-0.61bx
   ; Enable coverage collection in subprocesses spawned during tests.
   ; Works with parallel=true in .coveragerc so each process writes a separate data file.
   COVERAGE_PROCESS_START={toxinidir}/.coveragerc