[Integrated] RFR: 304: Squash additional commits into merge commits for merge PRs

[Robin Westberg]

Changeset: 92d7d97a
Author:    Robin Westberg <rwestberg at openjdk.org>
Date:      2020-03-20 07:06:26 +0000
URL:       https://git.openjdk.java.net/skara/commit/92d7d97a

304: Squash additional commits into merge commits for merge PRs

Reviewed-by: ehelin

! bots/pr/src/main/java/org/openjdk/skara/bots/pr/CheckRun.java
! bots/pr/src/main/java/org/openjdk/skara/bots/pr/PullRequestInstance.java
! bots/pr/src/test/java/org/openjdk/skara/bots/pr/MergeTests.java