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

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

third_party/git/t/t1412-reflog-loop.sh

@@ -0,0 +1,34 @@
+#!/bin/sh
+
+test_description='reflog walk shows repeated commits again'
+. ./test-lib.sh
+
+test_expect_success 'setup commits' '
+	test_tick &&
+	echo content >file && git add file && git commit -m one &&
+	git tag one &&
+	echo content >>file && git add file && git commit -m two &&
+	git tag two
+'
+
+test_expect_success 'setup reflog with alternating commits' '
+	git checkout -b topic &&
+	git reset one &&
+	git reset two &&
+	git reset one &&
+	git reset two
+'
+
+test_expect_success 'reflog shows all entries' '
+	cat >expect <<-\EOF &&
+		topic@{0} reset: moving to two
+		topic@{1} reset: moving to one
+		topic@{2} reset: moving to two
+		topic@{3} reset: moving to one
+		topic@{4} branch: Created from HEAD
+	EOF
+	git log -g --format="%gd %gs" topic >actual &&
+	test_cmp expect actual
+'
+
+test_done