2300: Do not list non-OpenJDK reviewers in Reviewers list

[zhaosongzs]

This PR is trying to make skara bot list non-recognized user in a separate section in the PR body.

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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-2300: Do not list non-OpenJDK reviewers in Reviewers list (Enhancement - P4)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/skara.git pull/1693/head:pull/1693
$ git checkout pull/1693

Update a local copy of the PR:
$ git checkout pull/1693
$ git pull https://git.openjdk.org/skara.git pull/1693/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 1693

View PR using the GUI difftool:
$ git pr show -t 1693

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/skara/pull/1693.diff

Webrev

Link to Webrev Comment