patch 9.1.0220: Few typos in source and test files

Problem:  Typos in code and tests.
Solution: Fix typos (zeertzjq).

closes: #14321

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_vim9_script.vim b/src/testdir/test_vim9_script.vim
index 77b8831..0e21334 100644
--- a/src/testdir/test_vim9_script.vim
+++ b/src/testdir/test_vim9_script.vim
@@ -4906,7 +4906,7 @@
   v9.CheckSourceFailure(lines, 'E1059: No white space allowed before colon: :number in range(10)', 2)
 enddef
 
-" This test used to cause an use-after-free memory access
+" This test used to cause a use-after-free memory access
 def Test_for_empty_line_after_lambda()
   var lines =<< trim END
     vim9script