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/libtest/lib3102.c

@@ -106,7 +106,7 @@ static CURLcode test_lib3102(const char *URL)
     return TEST_ERR_MAJOR_BAD;
   }
 
-  /* Set the HTTPS url to retrieve. */
+  /* Set the HTTPS URL to retrieve. */
   test_setopt(curl, CURLOPT_URL, URL);
 
   /* Capture certificate information */