Revert "CI: determine actual OpenSSL version dynamically"

This partially reverts commit ca1d09d258be9789efe2ed7085d3e1c9b44af6db.

The 2.5 does not compile with OpenSSL 3.0.7. So better to still use the
3.0.2 and don't use the latest OpenSSL version.

(cherry picked from commit a82a859f24f853c0c8431cdf46029f9746a1d8f3)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/.github/matrix.py b/.github/matrix.py
index 3b4ac0a..5c97efd 100644
--- a/.github/matrix.py
+++ b/.github/matrix.py
@@ -126,7 +126,7 @@
     for ssl in [
         "stock",
         "OPENSSL_VERSION=1.0.2u",
-        "OPENSSL_VERSION=latest",
+        "OPENSSL_VERSION=3.0.2",
         "LIBRESSL_VERSION=3.5.3",
 #        "BORINGSSL=yes",
     ]: