2328: Ignore bot user's comment when determining the latest action time of a PR

[zhaosongzs]

PullRequestPrunerBot is responsible for closing PRs that have not been active for a certain time. However, it currently doesn't ignore comments from bot users when determining the latest action time of a PR.

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Progress

• [ ] Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• [x] Change must not contain extraneous whitespace

Issue

• SKARA-2328: Ignore bot user's comment when determining the latest action time of a PR (Bug - P4)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/skara.git pull/1687/head:pull/1687
$ git checkout pull/1687

Update a local copy of the PR:
$ git checkout pull/1687
$ git pull https://git.openjdk.org/skara.git pull/1687/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 1687

View PR using the GUI difftool:
$ git pr show -t 1687

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/skara/pull/1687.diff

Webrev

Link to Webrev Comment