doc: Update RELEASING.md with current homebrew cask files (#4208)

* doc: Update RELEASING.md with current homebrew cask files

Signed-off-by: Stewart X Addison <sxa@redhat.com>

* Update brew section with automation information

Signed-off-by: Stewart X Addison <sxa@redhat.com>

* Reword sample PR text

Signed-off-by: Stewart X Addison <sxa@redhat.com>

* Link to homebrew autobump enablement

Signed-off-by: Stewart X Addison <sxa@redhat.com>

* Remove sample PR link as the PR is no longer there

Signed-off-by: Stewart X Addison <sxa@redhat.com>

---------

Signed-off-by: Stewart X Addison <sxa@redhat.com>

Author: sxa

RELEASING.md

@@ -372,15 +372,13 @@ Once all supported platform binaries have been released it's time to publish AQA
 
 4. Publish packages for different OS
 
-  4.1. **[Mac only]** Once the binaries are available on the website you need to update the Homebrew casks. There are 4 casks in total
-and all but the first one is in the `hombrew-cask-versions` repository. If you're doing a point release, the format of the version string is 11.0.20.1,1 so the version is always the same as "our" one but with the `+` replaced with a `,`
+  4.1. **[Mac only]** Once the binaries are available on the website there is now [automation upstream](https://github.com/Homebrew/homebrew-cask/commits/main/.github/workflows/autobump.yml) as of [June 2025](https://github.com/Homebrew/brew/pull/20117) which updates the Homebrew casks under the `BrewTestBot` ID - this automation should be checked to ensure it has run. Noting that for point releases (not tested with the automated PRs), the format of the version string should be 11.0.20.1,1 so the version is always the same as "our" one but with the `+` replaced with a `,`
 
 - [`temurin`](https://github.com/Homebrew/homebrew-cask/blob/master/Casks/t/temurin.rb) which always serves the latest release version
-- [`temurin8`](https://github.com/Homebrew/homebrew-cask-versions/blob/master/Casks/temurin8.rb)
-- [`temurin11`](https://github.com/Homebrew/homebrew-cask-versions/blob/master/Casks/temurin11.rb)
-- [`temurin17`](https://github.com/Homebrew/homebrew-cask-versions/blob/master/Casks/temurin17.rb)
-
-An example PR can be found [here](https://github.com/Homebrew/homebrew-cask-versions/pull/17582/files). The required SHA sums can be updated by `brew bump-cask-pr temurinXX --version 11.0.XX,Y` command if you're on a macos system, or manually if not . The separate pull request is required for each version you update. If in doubt reach out to @gdams as he's a maintainer.
+- [`temurin8`](https://github.com/Homebrew/homebrew-cask/blob/master/Casks/t/temurin@8.rb)
+- [`temurin11`](https://github.com/Homebrew/homebrew-cask/blob/master/Casks/t/temurin@11.rb)
+- [`temurin17`](https://github.com/Homebrew/homebrew-cask/blob/master/Casks/t/temurin@17.rb)
+- [`temurin21`](https://github.com/Homebrew/homebrew-cask/blob/master/Casks/t/temurin@21.rb)
 
   4.2. **[Linux only]** Once the binaries are available on the website you can begin updating the specfiles for the RPM/DEB/APK files. There are 4 different types of linux installer