Prior to this change, KIWI blindly synced the ESP directory into the
embedded ESP image. Depending on the distribution and packages included
for the created image, this can have undesirable side-effects.
For image builds that need some more fine-grained control over the
creation of the embedded ESP image (particularly for ISO images),
this change introduces the ability to inject an exclusion list
similar to what is used to filter out files for the root filesystem.
Fixes: https://github.com/OSInside/kiwi/issues/2008
Fixes: https://github.com/OSInside/kiwi/issues/2777
The sdist tarball produced by poetry build does not include
all files and skipped symlinks in test/data. This caused the
unit test run to fail if called from within that sources
The new optional metadata file image/exclude_files.yaml can
be placed inside of the local image root tree. At creation time of
the image binary the file contents are used to extend the default
exclude list with additional information. The structure of the
file must be as follows:
```yaml
exclude:
- exclude-name-used-in-rsync
```
