A recent commit from TranslateWiki added a app/src/main/res/values-x-invalidLanguageCode directory, which results in this build error:
app/src/main/res/values-x-invalidLanguageCode: Resource and asset merger: Invalid resource directory name
Maybe ks got deprecated as a language code and we should edit our TranslateWiki configuration? I believe we had similar issues in the past:
Workaround: Until the problem is fixed, when creating pull requests, feel free to remove that directory.