Revert "CI: update to the latest WolfSSL version"

This reverts commit 03f57fc.

Looks like the 5.7.4 version is broke with HAProxy, let's revert the CI
for now.

Author: wlallemand

.github/matrix.py

@@ -188,7 +188,7 @@ def main(ref_name):
             "OPENSSL_VERSION=1.0.2u",
             "OPENSSL_VERSION=1.1.1s",
             "QUICTLS=yes",
-            "WOLFSSL_VERSION=5.7.4",
+            "WOLFSSL_VERSION=5.7.0",
             "AWS_LC_VERSION=1.39.0",
             # "BORINGSSL=yes",
         ]