fix: Exclude aio module from coverage on Python 3.7

Add special coverage configuration for Python 3.7 that excludes
the aio module since it requires Python 3.8+ due to Starlette
dependency. This prevents coverage failures on Python 3.7.

Author: taeold

tox.ini

@@ -34,6 +34,8 @@ extras =
 setenv =
     PYTESTARGS = --cov=functions_framework --cov-branch --cov-report term-missing --cov-fail-under=100
     windows-latest: PYTESTARGS =
+    # Python 3.7: Exclude aio module from coverage since it requires Python 3.8+ (Starlette dependency)
+    py37: PYTESTARGS = --cov=functions_framework --cov-branch --cov-report term-missing --cov-fail-under=100 --cov-omit='*/aio/*'
 commands = pytest {env:PYTESTARGS} {posargs}
 
 [testenv:lint]
@@ -44,7 +46,8 @@ deps =
     isort
     mypy
     build
-extras = async
+extras =
+    async
 commands =
     black --check src tests conftest.py --exclude tests/test_functions/background_load_error/main.py
     isort -c src tests conftest.py