Update last JGit version

The jgit-last-release-version is used by japicmp as baseline.

Change-Id: If56cc1785b61c92c9a05c8c29c6cb62001e89218
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

pom.xml

@@ -182,7 +182,7 @@
     <maven.build.timestamp.format>yyyyMMddHHmm</maven.build.timestamp.format>
     <bundle-manifest>${project.build.directory}/META-INF/MANIFEST.MF</bundle-manifest>
 
-    <jgit-last-release-version>4.11.0.201803080745-r</jgit-last-release-version>
+    <jgit-last-release-version>5.1.0.201809111528-r</jgit-last-release-version>
     <apache-sshd-version>2.0.0</apache-sshd-version>
     <jsch-version>0.1.54</jsch-version>
     <jzlib-version>1.1.1</jzlib-version>