patch 8.2.3675: using freed memory when vim_strsave() fails

Problem:    Using freed memory when vim_strsave() fails.
Solution:   Clear "last_sourcing_name".  Check for msg_source() called
            recursively. (closes #8217)
diff --git a/src/version.c b/src/version.c
index 6d96d43..07d93d9 100644
--- a/src/version.c
+++ b/src/version.c
@@ -758,6 +758,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3675,
+/**/
     3674,
 /**/
     3673,