Merge pull request #6938 from ThomasWaldmann/fix-warnings2-master

make setuptools happy, fixes #6874 (try 2, same as in 1.2-maint)

setup.cfg

@@ -32,7 +32,7 @@ project_urls =
     Source Code = https://github.com/borgbackup/borg
 
 [options]
-packages = find:
+packages = find_namespace:
 package_dir =
     =src
 python_requires = >=3.9

src/borg/cache_sync/__init__.py

@@ -1,23 +0,0 @@
-"""
-dummy package init file to suppress this weird setuptools warning:
-
-$ pip install -v .  # note: does not happen with -ve .
-
-############################
-# Package would be ignored #
-############################
-Python recognizes 'borg.cache_sync' as an importable package,
-but it is not listed in the `packages` configuration of setuptools.
-
-'borg.cache_sync' has been automatically added to the distribution only
-because it may contain data files, but this behavior is likely to change
-in future versions of setuptools (and therefore is considered deprecated).
-
-Please make sure that 'borg.cache_sync' is included as a package by using
-the `packages` configuration field or the proper discovery methods
-(for example by using `find_namespace_packages(...)`/`find_namespace:`
-instead of `find_packages(...)`/`find:`).
-
-You can read more about "package discovery" and "data files" on setuptools
-documentation page.
-"""