[PR aio-libs#7684/c0ba7e53 backport][3.9] Make setup.cfg packages exp…

…licit (aio-libs#7687)

**This is a backport of PR aio-libs#7684 as merged into master
(c0ba7e5).**

setup.cfg

@@ -41,7 +41,7 @@ classifiers =
 
 [options]
 python_requires = >=3.8
-packages = find:
+packages = aiohttp
 # https://setuptools.readthedocs.io/en/latest/setuptools.html#setting-the-zip-safe-flag
 zip_safe = False
 include_package_data = True