Keep comments on the txt export when updating plugins

### What feature do you want to see added?

As you can see in https://github.com/jenkins-infra/docker-jenkins-weekly/pull/513#issuecomment-1155381505,
the use of the command `java -jar "${TMP_DIR}/jenkins-plugin-manager.jar" -f plugins.txt --available-updates --output txt --war "${TMP_DIR}/jenkins.war" > plugins2.txt` (ref. https://github.com/jenkins-infra/docker-jenkins-weekly/blob/main/bin/update-plugins.sh) does not keep the comment from the source plugin file.

Not sure if there is a solution currently (using YAML, inlining comment, something else)?

If no solution, would it be possible to provide a `--write-file` / `--inplace` flag that would write the source plugin file in place?

### Upstream changes

_No response_