Remove deprecated api method FileContents::inPackageInfo from code

[romani]

deprecafed in 10.2 (april 2022) f6a15cf#diff-0910ced16436543c1477e7a3528483b46612a86971ff771893e89700f85dfb3dR335

deprecation issue - #11507

We need to find some major version update time, and remove such methods from our API.
We need to recheck plugins(maven, eclipse-cs, sonar, ...... gradle, idea.....) if they need to be updated or notify/help them to upgrade.

issue is created based on conversation :
#11639

[rnveach]

maven, eclipse-cs, sonar, sevntu

None of these use this method.

gradle, idea

Unknown.