Update jgit to f2e5bace4841758927d47db7d20e4a6f7353ce57

This includes the following jgit changes:

003862722 LockFile: create OutputStream only when needed
  this fixes  "Too many open files" errors when
  - fetching repos with many refs [1]
  - converting from reftable back to refdir format [2]

540b29bf4 Remove ReftableNumbersNotIncreasingException

[1] https://bugs.eclipse.org/bugs/show_bug.cgi?id=552173
[2] https://bugs.eclipse.org/bugs/show_bug.cgi?id=573328

Change-Id: If29ffa24e3c5ba244578e2b4f1ed74efa6b3a8ba
diff --git a/modules/jgit b/modules/jgit
index 8f422e9..f2e5bac 160000
--- a/modules/jgit
+++ b/modules/jgit
@@ -1 +1 @@
-Subproject commit 8f422e9a9add4a7a7d972e8aa1dfa5e15fccdf99
+Subproject commit f2e5bace4841758927d47db7d20e4a6f7353ce57