Re-update libgit2 to master branch

alexcrichton · alexcrichton · commit e245130e5ae2 · 2020-07-21T15:48:24.000-07:00
Forgot that we were ahead of 1.0.1!
diff --git a/libgit2-sys/libgit2 b/libgit2-sys/libgit2
@@ -1 +1 @@
-Subproject commit 0ced29612dacb67eefe0c562a5c1d3aab21cce96
+Subproject commit a83fd5107879d18b31ff8173ea062136256321be
