merge(third_party/git): Merge squashed git subtree at v2.23.0

Merge commit '1b593e1ea4' as 'third_party/git'

third_party/git/t/t9135-git-svn-moved-branch-empty-file.sh

@@ -0,0 +1,20 @@
+#!/bin/sh
+
+test_description='test moved svn branch with missing empty files'
+
+. ./lib-git-svn.sh
+test_expect_success 'load svn dumpfile'  '
+	svnadmin load "$rawsvnrepo" < "${TEST_DIRECTORY}/t9135/svn.dump"
+	'
+
+test_expect_success 'clone using git svn' 'git svn clone -s "$svnrepo" x'
+
+test_expect_success 'test that b1 exists and is empty' '
+	(
+		cd x &&
+		git reset --hard origin/branch-c &&
+		test_must_be_empty b1
+	)
+	'
+
+test_done