RFR: 2107: Change naming of branches created by /backport command

[Zhao Song]

On Wed, 22 Nov 2023 00:01:18 GMT, Zhao Song <zsong at openjdk.org> wrote:

> Since in [JDK-8320358](https://bugs.openjdk.org/browse/JDK-8320358), the GitHub action would ignore the branches whose name start with 'jdk', we should change the naming of branches created by backport command.

Thanks!

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PR Comment: https://git.openjdk.org/skara/pull/1588#issuecomment-1823378533