chore(python): update minimum Python version to 3.10

OpenFeature Python SDK is dropping 3.9 support in the upcoming 0.9.0
release. Update to 3.10+ to stay aligned.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: nicklasl

openfeature-provider/python/pyproject.toml

@@ -8,7 +8,7 @@ version = "0.2.1"
 description = "Confidence OpenFeature provider for local flag resolution using WebAssembly"
 readme = "README.md"
 license = "Apache-2.0"
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 authors = [
     { name = "Spotify", email = "confidence@spotify.com" }
 ]
@@ -18,7 +18,6 @@ classifiers = [
     "Intended Audience :: Developers",
     "License :: OSI Approved :: Apache Software License",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
@@ -67,7 +66,7 @@ asyncio_mode = "auto"
 testpaths = ["tests"]
 
 [tool.mypy]
-python_version = "3.9"
+python_version = "3.10"
 warn_unused_configs = true
 warn_redundant_casts = true
 strict_equality = true
@@ -95,7 +94,7 @@ disable_error_code = ["attr-defined", "name-defined", "union-attr", "operator",
 
 [tool.ruff]
 line-length = 88
-target-version = "py39"
+target-version = "py310"
 exclude = [".venv", ".git", "*_pb2.py", "*_pb2_grpc.py"]
 
 [tool.ruff.lint]