ci: support gradle dependency caching in workflows

[MostafaMohamed2002]

Contributor checklist

• This pull request is on a separate branch and not the main branch
• I have tested my code with the ./gradlew lintKotlin detekt test command as directed in the testing section of the contributing guide

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Description

This PR adds support for caching Gradle dependencies in CI workflows to improve build performance.

Related issue

• Use Gradle Caching in GitHub Actions Workflows  #212

[github-actions]

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Maintainer checklist

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[angrezichatterbox]

Great PR @MostafaMohamed2002. Everything looks good to me. With this change, we would finally have faster workflows. Thanks :)

[andrewtavis]

Really appreciate you thinking of this and executing, @MostafaMohamed2002! Great to have you on the project 😊