Dependabot-core: Gradle: add support for dependencies in buildSrc

[Tapchicoma]

Gradle has a concept of buildSrc (https://docs.gradle.org/current/userguide/organizing_gradle_projects.html#sec:build_sources) that provides logic for the project build files.

Also it is possible to define there a dependencies (even using common Kotlin files): https://github.com/JLLeitschuh/ktlint-gradle/blob/master/plugin/buildSrc/src/main/kotlin/PluginDependencies.kt

Please add support to updating dependencies defined in buildSrc folder in Groovy, Java or Kotlin file (please also keep in mind closed dependabot/feedback#392)

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs within seven days. Thank you for your contributions.

[JavierSegoviaCordoba]

Gradle 6.8 will include a new official dependencies management.

Source: https://github.com/gradle/gradle/pull/14896

[sindrenm]

Apologies for bumping this thread, but I felt it was worth mentioning that the new dependencies management moved over to the 7.0 RC1 milestone on December 8. In case you're already on 6.8 and want to try this out, as I was. Further progress is tracked in https://github.com/gradle/gradle/issues/15352.