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/test265

@@ -47,22 +47,22 @@ daniel
 
 # then this is returned when we get proxy-auth
 <data1000>
-HTTP/1.1 200 OK swsbounce
+HTTP/1.1 200 OK swsbounce%CR
 Server: no
-
+%CR
 Nice proxy auth sir!
 </data1000>
 
 <datacheck>
-HTTP/1.0 407 Authorization Required to proxy me my dear
-Proxy-Authenticate: NTLM TlRMTVNTUAACAAAAAgACADAAAACGggEAc51AYVDgyNcAAAAAAAAAAG4AbgAyAAAAQ0MCAAQAQwBDAAEAEgBFAEwASQBTAEEAQgBFAFQASAAEABgAYwBjAC4AaQBjAGUAZABlAHYALgBuAHUAAwAsAGUAbABpAHMAYQBiAGUAdABoAC4AYwBjAC4AaQBjAGUAZABlAHYALgBuAHUAAAAAAA==
-Connection: Keep-Alive
-Content-Length: 1033
-
-HTTP/1.1 200 Things are fine in proxy land
-Server: Microsoft-IIS/5.0
-Content-Type: text/html; charset=iso-8859-1
-
+HTTP/1.0 407 Authorization Required to proxy me my dear%CR
+Proxy-Authenticate: NTLM TlRMTVNTUAACAAAAAgACADAAAACGggEAc51AYVDgyNcAAAAAAAAAAG4AbgAyAAAAQ0MCAAQAQwBDAAEAEgBFAEwASQBTAEEAQgBFAFQASAAEABgAYwBjAC4AaQBjAGUAZABlAHYALgBuAHUAAwAsAGUAbABpAHMAYQBiAGUAdABoAC4AYwBjAC4AaQBjAGUAZABlAHYALgBuAHUAAAAAAA==%CR
+Connection: Keep-Alive%CR
+Content-Length: 1033%CR
+%CR
+HTTP/1.1 200 Things are fine in proxy land%CR
+Server: Microsoft-IIS/5.0%CR
+Content-Type: text/html; charset=iso-8859-1%CR
+%CR
 HTTP/1.1 200 OK
 Date: Tue, 09 Nov 2010 14:49:00 GMT
 Content-Length: 7