patch 9.0.0828: various typos

Problem:    Various typos.
Solution:   Correct typos. (closes #11432)
diff --git a/src/testdir/test_vim9_cmd.vim b/src/testdir/test_vim9_cmd.vim
index 4e89c7f..0fe6e7c 100644
--- a/src/testdir/test_vim9_cmd.vim
+++ b/src/testdir/test_vim9_cmd.vim
@@ -126,7 +126,7 @@
   END
   v9.CheckScriptSuccess(lines)
 
-  # "legacy" does not aply to a called function
+  # "legacy" does not apply to a called function
   lines =<< trim END
       vim9script