Revert "Upgrade JGit to 5.1.10.201908230655-r"

This reverts commit 13f55abe3c.

Reason for revert: The upgrade broke OnlineNoteDbMigrationIT.

Bug: Issue 11373
Change-Id: I8191456cafd8e670a0e38e98bca0efde752419ff

lib/jgit/jgit.bzl

@@ -1,6 +1,6 @@
 load("//tools/bzl:maven_jar.bzl", "MAVEN_CENTRAL", "maven_jar")
 
-_JGIT_VERS = "5.1.10.201908230655-r"
+_JGIT_VERS = "5.1.7.201904200442-r"
 
 _DOC_VERS = _JGIT_VERS  # Set to _JGIT_VERS unless using a snapshot
 
@@ -40,28 +40,28 @@ def jgit_maven_repos():
         name = "jgit-lib",
         artifact = "org.eclipse.jgit:org.eclipse.jgit:" + _JGIT_VERS,
         repository = _JGIT_REPO,
-        sha1 = "f31edd6f2fb29f71e99e032371620e133182b279",
-        src_sha1 = "59007bae013106211ba6168e2c977baa2ec30045",
+        sha1 = "ef1f744a1117e3d8916f3770486502a56d241b16",
+        src_sha1 = "7bf5b5298f8936e959a92f62b5151d58feb9c00a",
         unsign = True,
     )
     maven_jar(
         name = "jgit-servlet",
         artifact = "org.eclipse.jgit:org.eclipse.jgit.http.server:" + _JGIT_VERS,
         repository = _JGIT_REPO,
-        sha1 = "ae18143349233cb08968ed09457d2cbdef191e90",
+        sha1 = "8306e221fb50985247138adb8ffb0f4cd74c5e9a",
         unsign = True,
     )
     maven_jar(
         name = "jgit-archive",
         artifact = "org.eclipse.jgit:org.eclipse.jgit.archive:" + _JGIT_VERS,
         repository = _JGIT_REPO,
-        sha1 = "e2c57117cfec84ace6777365c345e200e41e8b3b",
+        sha1 = "fefb13ab8331cc8b13a15b653b1e057de7d3e514",
     )
     maven_jar(
         name = "jgit-junit",
         artifact = "org.eclipse.jgit:org.eclipse.jgit.junit:" + _JGIT_VERS,
         repository = _JGIT_REPO,
-        sha1 = "dab29b14a9e61998667af0bcc3a9e5a67f58b115",
+        sha1 = "f73f1eacc38f8329d9453f1d0353e82404379a89",
         unsign = True,
     )