patch 8.2.4857: Yaml indent for multiline is wrong

Problem:    Yaml indent for multiline is wrong.
Solution:   Adjust patterns. (closes #10328, closes #8740)
diff --git a/runtime/indent/testdir/yaml.ok b/runtime/indent/testdir/yaml.ok
index 5ca2871..becdb1b 100644
--- a/runtime/indent/testdir/yaml.ok
+++ b/runtime/indent/testdir/yaml.ok
@@ -17,3 +17,9 @@
 map: multiline
   value
 # END_INDENT
+
+# START_INDENT
+map: |
+  line1
+  line2
+# END_INDENT