Upgrade JGit to 5.1.13.202002110435-r

Aligns with the version used starting from core Gerrit 2.16.17.

Change-Id: I2578e1a2b30f7c805ea17ed97c58ab226d1eb55c

external_plugin_deps.bzl

diff --git a/external_plugin_deps.bzl b/external_plugin_deps.bzl
index 96504a2..561a621 100644
--- a/external_plugin_deps.bzl
+++ b/external_plugin_deps.bzl
@@ -125,8 +125,8 @@
     maven_jar(
         name = "jgit",
         artifact =
-            "org.eclipse.jgit:org.eclipse.jgit:5.1.12.201910011832-r",
-        sha1 = "62c60aa985aa8dcfa6ad7308d130c319a1d01073",
+            "org.eclipse.jgit:org.eclipse.jgit:5.1.13.202002110435-r",
+        sha1 = "dc99e6ef37038090561bd5253c71b150791bea58",
     )
 
     maven_jar(