Do not run gradle-cache-action if project/repo does not use Gradle

[mkurz]

The Gradle Cache always runs, no matter if the project is using Gradle or not:
https://github.com/playframework/play-mailer/actions/runs/14854450285/job/41704377293#step:6:29

Even worse, if there is a problem, like timeout, it can take long time until the actions finishes:
https://github.com/sbt/sbt-web-build-base/actions/runs/15442013973/job/43461980655?pr=76#step:6:29

here it took more than 500 seconds...

Can we somehow skip the Gradle action with and if: ... condition? Not sure what we could use as condition, something like if repo does not contain a file named *.gradle.kts or *.gradle?

.github/.github/workflows/cmd.yml

Lines 130 to 137 in 6aef3f2

	- name: Gradle Cache
	uses: burrunan/gradle-cache-action@v3
	with:
	build-root-directory: ${{ inputs.gradle-build-root }}
	# Disable caching of ~/.gradle/caches/build-cache-*
	save-local-build-cache: false
	# Disable caching of ~/.m2/repository/
	save-maven-dependencies-cache: false

@ihostage What do you think?

[ihostage]

Hi, Matthias! Yep, I also thought about gradle cache. It was my second point that I want to check in #101. I just need a find time to make a few experiments 🤪