Add parsing for Record Size Limit extension in TLS 1.3

Fixes #7007

Signed-off-by: Jan Bruckner <jan@janbruckner.de>
diff --git a/scripts/config.py b/scripts/config.py
index a53c470..404a5ef 100755
--- a/scripts/config.py
+++ b/scripts/config.py
@@ -215,6 +215,7 @@
     'MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN', # build dependency (clang+memsan)
     'MBEDTLS_TEST_CONSTANT_FLOW_VALGRIND', # build dependency (valgrind headers)
     'MBEDTLS_X509_REMOVE_INFO', # removes a feature
+    'MBEDTLS_SSL_RECORD_SIZE_LIMIT', # in development, currently breaks other tests
 ])
 
 def is_seamless_alt(name):