patch 9.1.1325: tests: not checking error numbers properly

Problem:  tests: not checking error numbers properly.
Solution: Add a trailing comma to avoid matching a different error
          number with the same prefix (zeertzjq)

closes: #17159

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_crypt.vim b/src/testdir/test_crypt.vim
index 85ed574..f056e38 100644
--- a/src/testdir/test_crypt.vim
+++ b/src/testdir/test_crypt.vim
@@ -344,7 +344,7 @@
     " should fail
     norm! u
     call assert_match('Already at oldest change', execute(':1mess'))
-    call assert_fails('verbose rundo ' .. fnameescape(ufile), 'E822')
+    call assert_fails('verbose rundo ' .. fnameescape(ufile), 'E822:')
     bw!
     set undolevels& cryptmethod& undofile&
     call delete('Xcrypt_sodium_undo.txt')
@@ -357,8 +357,8 @@
     return
   endif
   sp Xcrypt_sodium_undo.txt
-  call assert_fails(':set cryptmethod=xchacha20', 'E474')
-  call assert_fails(':set cryptmethod=xchacha20v2', 'E474')
+  call assert_fails(':set cryptmethod=xchacha20', 'E474:')
+  call assert_fails(':set cryptmethod=xchacha20v2', 'E474:')
   bw!
   set cm&
 endfunc