git: openjdk/skara: Use the web url in the displayed fetch command

[duke]

Changeset: ab9a473b
Author:    Robin Westberg <rwestberg at openjdk.org>
Date:      2019-08-07 10:12:35 +0000
URL:       https://git.openjdk.java.net/skara/commit/ab9a473b

Use the web url in the displayed fetch command

Reviewed-by: ehelin

! bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/PullRequestInstance.java