pytest: enable in 5 GHA jobs, fix fallouts

They take about 4.5 minutes of CI time in GHA/macos.

Also:
- autotools: improve `caddy`, `vsftpd` detection.
  Bringing it closer to cmake.
- autotools: fix `--with-test-caddy=no`, `--with-test-vsftps=no`,
  `--with-test-nghttpx=no` options.
- cmake: sync `nghttpx` default with autotools.
- pytest: disable failing mbedTLS tests on macOS CI.
- pytest: disable failing earlydata tests on macOS CI.
- GHA/macos: keep vsftpd pytests disabled due to lengthy run times.
- pytest: fix test_05_04 for LibreSSL. Ref: #17367
  Authored-by: Stefan Eissing

Remaining issues:
- some unidentified tests taking a long time with mbedTLS:
  `================= 462 passed, 278 skipped in 347.93s (0:05:47) =================`
  Ref: https://github.com/curl/curl/actions/runs/15073354301/job/42374999041#step:17:1536
  Workaround: not enabling pytest for mbedTLS jobs
- 17 FTP tests taking a long time (affecting all TLS backends):
  without vsftpd:
  `====================== 496 passed, 244 skipped in 56.15s =======================`
  Ref: https://github.com/curl/curl/actions/runs/15073354301/job/42374998230#step:17:1536
  with vsftpd:
  `================= 513 passed, 227 skipped in 409.37s (0:06:49) =================`
  Ref: https://github.com/curl/curl/actions/runs/15073678568/job/42376039672?pr=17362#step:17:1537
  Workaround: force-disable vsftpd.
- 100 tests failing with SecureTransport. Let's ignore that due to imminent deprecation.
  Ref: https://github.com/curl/curl/actions/runs/15055652333/job/42320873732#step:17:15362

Follow-up to 30ef79ed93 #17295
Follow-up to 9147903366 #16518

Closes #17362

tests/http/testenv/env.py

@@ -33,7 +33,7 @@ import subprocess
 import tempfile
 from configparser import ConfigParser, ExtendedInterpolation
 from datetime import timedelta
-from typing import Optional, Dict
+from typing import Optional, Dict, List
 
 import pytest
 from filelock import FileLock
@@ -329,6 +329,13 @@ class Env:
     def curl_uses_lib(libname: str) -> bool:
         return libname.lower() in Env.CONFIG.curl_props['libs']
 
+    @staticmethod
+    def curl_uses_any_libs(libs: List[str]) -> bool:
+        for libname in libs:
+            if libname.lower() in Env.CONFIG.curl_props['libs']:
+                return True
+        return False
+
     @staticmethod
     def curl_uses_ossl_quic() -> bool:
         if Env.have_h3_curl():
@@ -389,10 +396,7 @@ class Env:
 
     @staticmethod
     def curl_can_early_data() -> bool:
-        return Env.curl_uses_lib('gnutls') or \
-            Env.curl_uses_lib('wolfssl') or \
-            Env.curl_uses_lib('quictls') or \
-            Env.curl_uses_lib('openssl')
+        return Env.curl_uses_any_libs(['gnutls', 'wolfssl', 'quictls', 'openssl'])
 
     @staticmethod
     def curl_can_h3_early_data() -> bool: