RFR: 8314656: GHA: No need for Debian ports keyring installation after JDK-8313701 [v2]

[Aleksey Shipilev]

> There is no need for keyring installation after [JDK-8313701](https://bugs.openjdk.org/browse/JDK-8313701). We can simplify that part to reduce the difference between different JDK releases.
> 
> Additional testing:
>  - [ ] GHA

Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains one commit:

  Fix

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Changes: https://git.openjdk.org/jdk/pull/15362/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15362&range=01
  Stats: 3 lines in 1 file changed: 0 ins; 2 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/15362.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15362/head:pull/15362

PR: https://git.openjdk.org/jdk/pull/15362