badwords: fix issues found in tests

There remain some false positives, hits in test data, and `dir` use,
around 100 issues in total.

There is no plan to enforce badwords on tests.

Also:
- badwords.txt: let a few `manpage[s]` occurrences through
  (in Perl code).

Closes #19541

tests/data/test458

@@ -36,7 +36,7 @@ FUNVALUE=contents%TESTNUMBER
 VALUE2=curl
 </setenv>
 <name>
-variable expand the file name with --expand-output
+variable expand the filename with --expand-output
 </name>
 <file name="%LOGDIR/cmd">
 --variable %FUNVALUE