Move pytest warning enable into pyproject.toml

Wasn't sure on the syntax for this before, so just went with the CLI
invocation. I think we just want this (by default) on any `pytest`
invocation.

Signed-off-by: Stefan VanBuren <svanburen@buf.build>

Author: stefanvanburen

justfile

@@ -21,7 +21,7 @@ typecheck:
 
 # Run unit tests
 test *args:
-    uv run pytest -W error {{ args }}
+    uv run pytest {{ args }}
 
 # Run lint, typecheck and test
 check: lint typecheck test

pyproject.toml

@@ -82,6 +82,8 @@ module-name = "connectrpc"
 strict = true
 testpaths = ["test"]
 timeout = "1800"     # 30 min
+# Turn all warnings into errors
+filterwarnings = ["error"]
 
 [tool.ruff.format]
 skip-magic-trailing-comma = true