build: fix installing of code-signing identity on macOS (#27266)

Co-authored-by: Milan Burda <[email protected]>

script/codesign/codesign.cnf

@@ -1,7 +1,7 @@
 [req]
 default_bits = 4096
 encrypt_key = no
-default_md = 512
+default_md = sha512
 distinguished_name = req_distinguished_name
 prompt = no