Jochen Sprickerhof a9a336a12b Don't allow '_' in first place of version code ...

Fixes a regression of 2cb0ff45. Example:

versionCode project.versionCode_plus

931b0a3087/app/build.gradle (L38)

2021-06-09 11:04:25 +00:00

..

build.gradle

Don't allow '_' in first place of version code

2021-06-09 11:04:25 +00:00