pmbootstrap downloads APKINDEX files for all arches in strict mode

Example:

$ pmbootstrap build hello-world --force --strict
[15:32:25] Cleared up ~0 MB of space
[15:32:26] Update package index for armv7, aarch64, x86 (12 file(s))

Here it should only need the x86_64 APKINDEX files (which it had just downloaded in another call). All other arches are not relevant for this package, yet it tries to grab the index files for them.