prefer export.companionFileTemplatePath if the value is given

[LucaGobbo]

This is how the functionality actually should work,

I want the following to also work:

• I want the parent directories, to get the correct Contents.json file (which is driven by useXcodeAssetCompanionFile)
• I also want to be able to use a custom companion template, which get ignored when I pass true for useXcodeAssetCompanionFile

alternatives:

1. • add a new flag to the Config which indicates these Content.json files for directories need to be created
2. • add a new flag that indicates we should prefer the companionFileTemplatePath over the one provided when you set useXcodeAssetCompanionFile to true

These options add more flags to the config, so I opted for the solution I provided in this PR

[github-actions]

Test Results

2 tests   2 ✅  18s ⏱️
2 suites  0 💤
2 files    0 ❌

Results for commit 479fe7e.