RFR: 1465: Using altfixversions prevents commit comments

[Magnus Ihse Bursie]

On Mon, 6 Jun 2022 09:56:30 GMT, Erik Joelsson <erikj at openjdk.org> wrote:

> The altfixversions feature introduced in [SKARA-1213](https://bugs.openjdk.java.net/browse/SKARA-1213) had the unfortunate side effect of also blocking additional commit comments from being added to existing backports. I think this needs to be fixed as those additional commit comments help integrators track where and when changes move between different repos.
> 
> This patch fixes this and adjusts the relevant test.

LGTM

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Marked as reviewed by ihse (Reviewer).

PR: https://git.openjdk.java.net/skara/pull/1330