tests: replace remaining CR bytes with the new macro %CR

There is no more mixed-newline file in the repository after this patch.
Except for`.bat` and `.sln` files (4 in total), all files use LF
newlines.

Also:
- `spacecheck.pl`: drop mixed-EOL exception for test data.
- runtests: add option `-w` to check if test data has stray CR bytes in
  them.
- build: enable the option above in test targets, except the CI-specific
  one where `spacecheck.pl` does this job already.
- tested OK (with expected failures) in CI with stray CRs added.
- cmake: enable option `-a` for the `tests` target. To continue testing
  after a failed test.

Follow-up to 63e9721b63 #19313
Follow-up to 6cf3d7b1b1 #19318
Follow-up to 4d2a05d3fe #19284

Closes #19347

tests/data/test433

@@ -9,10 +9,10 @@
 # Server-side
 <reply>
 <data>
-HTTP/1.1 200 OK
-Content-Length: 6
-Content-Type: text/1
-
+HTTP/1.1 200 OK%CR
+Content-Length: 6%CR
+Content-Type: text/1%CR
+%CR
 -foo-
 </data>
 </reply>