"pkgrel_bump --auto": Handle subpackages properly

Created by: ollieparanoid

pmbootstrap pkgrel_bump --auto automatically increases the pkgrel for packages linking against libraries, which don't exist anymore (because the soname has been changed). The feature is explained in detail in

The previous implementation did not detect soname breakage, when a subpackage linked against a certain library, but the main package did not (e.g. qt5-qtbase-mysql and qt5-qtbase). This was, because we iterated over the aports/* to find the packages to be checked.

To fix this, we are iterating over the packages found in the APKINDEX files instead (of both the locally compiled packages and the downloaded index from the pmOS mirror).

Details:

• pmb/helpers/pkgrel_bump.py:
  • Rewrite auto_apkindex_package() to act upon a given parsed aport and apk (from the index) instead of finding the apk dict by itself (we need it earlier anyway).
  • Rewrite auto() to iterate over APKINDEX files instead of aports
    • Skip packages already found, so the pkgrel does not get increased multiple times when the same package was found in multipe index files.
• Put the package name at the beginning of the log messages to make them more readable
• testdata: Create a new testsubpkg aport, where only the subpackage links against testlib
• Adjust testing code to test everything with testsubpkg as well.

NOTE: This makes the command a bit slower, but we could improve performance again by smart caching of pmb.parse.apkindex.depends(). This could come in a future PR, the important part here is that the command is bug-free again with this fix.

Fixes #1379 (closed).