patch 8.2.1912: with Python 3.9 some tests fail

Problem:    With Python 3.9 some tests fail.
Solution:   Take into account the different error message. (James McCoy,
            closes #7210)
diff --git a/src/version.c b/src/version.c
index 2137000..adef583 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1912,
+/**/
     1911,
 /**/
     1910,