[Integrated] RFR: Filter out PR-headers before sending mails

[duke]

Changeset: cd61be82
Author:    Robin Westberg <rwestberg at openjdk.org>
Date:      2019-09-17 10:49:22 +0000
URL:       https://git.openjdk.java.net/skara/commit/cd61be82

Filter out PR-headers before sending mails

Reviewed-by: ehelin

! bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/ArchiveWorkItem.java
! bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/ReviewArchive.java
! bots/mlbridge/src/test/java/org/openjdk/skara/bots/mlbridge/MailingListBridgeBotTests.java
! email/src/main/java/org/openjdk/skara/email/EmailBuilder.java