RFR: 7903500: Add Gradle Wrapper Validation workflow to jtreg [v2]

Mon Jun 26 14:41:31 UTC 2023

On Fri, 23 Jun 2023 16:01:48 GMT, Christian Stein <cstein at openjdk.org> wrote:

>> This change adds a workflow to this repository to verify that any and all `gradle-wrapper.jar` files in the repository match the SHA-256 checksums of any of our official releases. See details at https://github.com/marketplace/actions/gradle-wrapper-validation
>
> Christian Stein has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Update gradle-wrapper-validation.yml
>   
>   Fine-tune event triggers

Approved, per @kevinrushforth

-------------

Marked as reviewed by jjg (Lead).

PR Review: https://git.openjdk.org/jtreg/pull/159#pullrequestreview-1498710283