GitHub Action: upgrade LLVM, GCC, Java and Ubuntu

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GitHub Action supports Ubuntu 26.04 image as a "Public Review" for 1 month:

• Ubuntu2604-Readme.md
• Ubuntu 26.04 and Ubuntu 26.04 Arm is now available as a public preview
• GitHub-hosted runners reference mentions ubuntu-26.04 as a "Public preview"

I created #152717 to test if it would be possible to upgrade Ubuntu 24.04 to 26.04. I had multiple issues.

To prepare our workflow for Ubuntu 26.04, I propose to start with:

• Upgrade LLVM from 19, 20 or 21 to LLVM 20: PR gh-152785: Upgrade LLVM to LLVM 22 in GitHub Action #152781.
• Upgrade Java from 17 to 21: PR gh-152785: Upgrade Java from 17 to 21 in GHA Android #152783.
• Upgrade GCC from 10 to 13 in Address Sanitizer: PR gh-152785: Upgrade GCC from 10 to 13 in GHA Address Sanitizer #152782.

Linked PRs

• gh-152785: [WIP] Upgrade Ubuntu from 24.04 to 26.04 in GitHub Actions #152717
• gh-152785: Upgrade LLVM to LLVM 22 in GitHub Action #152781
• gh-152785: Upgrade GCC from 10 to 13 in GHA Address Sanitizer #152782
• gh-152785: Upgrade Java from 17 to 21 in GHA Android #152783