This is needed to add ability to enable `FIR_DUMP` directive which
  may be helpful in investigating bugs

It prevents missing inference session for local declaration (local functions, local classes or objects)

^KT-44801 Fixed

Gradle also removes these configurations in 7.0. See gradle/gradle@2cb45cdbd0756b718a17918abd1773e816f40551
#KT-44462 Fixed

#KT-43556 Fixed

Replace direct Gradle property access to provider usage. See https://docs.gradle.org/6.8.2/userguide/configuration_cache.html#config_cache:requirements:undeclared_gradle_prop_read

#KT-42911 Fixed

It's removed as those tasks now support Gradle configuration cache

FileSystemOperations is available since Gradle 6.0. ArchiveOperations usage is also refactored. Integration tests Gradle version requirements are reverted.

#KT-43804 Fixed

#KT-37586 Fixes

#EA-6040509 Fixed