Upgrade JGit to 4.9.2.201712150930-r.15-g5fe8e31d4

This aligns with the version used in core Gerrit's stable-2.15
branch.

Change-Id: I429d213b494eacbbf628d7fa18904c14140c039b
diff --git a/external_plugin_deps.bzl b/external_plugin_deps.bzl
index 065ccfd..687e647 100644
--- a/external_plugin_deps.bzl
+++ b/external_plugin_deps.bzl
@@ -1,13 +1,13 @@
 load("//tools/bzl:maven_jar.bzl", "maven_jar", "GERRIT", "MAVEN_LOCAL", "MAVEN_CENTRAL")
 
-JGIT_VERSION = '4.9.2.201712150930-r.4-g085d1f959'
+JGIT_VERSION = '4.9.2.201712150930-r.15-g5fe8e31d4'
 REPO = GERRIT
 
 def external_plugin_deps():
   maven_jar(
     name = 'jgit_http_apache',
     artifact = 'org.eclipse.jgit:org.eclipse.jgit.http.apache:' + JGIT_VERSION,
-    sha1 = '13859b30c8a20eb99dca3b9d2bb595e82d90320b',
+    sha1 = '0d8b34c089d419ff0ea6540c9c35a796d0454ab3',
     repository = REPO,
     unsign = True,
     exclude = [
@@ -19,7 +19,7 @@
   maven_jar(
     name = 'jgit_lfs',
     artifact = 'org.eclipse.jgit:org.eclipse.jgit.lfs:' + JGIT_VERSION,
-    sha1 = '70dea6582f956fbaea003391fac8d79d280a9d24',
+    sha1 = 'e11b50bbef951b7a306dc8e84ca41128526d330c',
     repository = REPO,
     unsign = True,
     exclude = [
@@ -31,7 +31,7 @@
   maven_jar(
     name = 'jgit_lfs_server',
     artifact = 'org.eclipse.jgit:org.eclipse.jgit.lfs.server:' + JGIT_VERSION,
-    sha1 = '1e704bf986e2f882666ca3b8ae1446137346b8ee',
+    sha1 = '23a001273801f8866a69c328bb194ad663d92fca',
     repository = REPO,
     unsign = True,
     exclude = [