RFR: Fix jextract GHA [v2]

Fri Apr 29 11:41:06 UTC 2022

On Fri, 29 Apr 2022 11:33:39 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

>> There are a couple of issue with the jextract GHA:
>> * the action does not ignore pr/* branches, which seems to be the norm in JDK
>> * the build is still referring to the old variable name `libclang_home` instead of `llvm_home`
>
> Maurizio Cimadamore has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fix broken `ifOnly`

Marked as reviewed by jvernee (no project role).

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PR: https://git.openjdk.java.net/jextract/pull/28