Record size limit support is released, so remove warning about only for testing

Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
diff --git a/include/mbedtls/mbedtls_config.h b/include/mbedtls/mbedtls_config.h
index dfc7b6e..3592141 100644
--- a/include/mbedtls/mbedtls_config.h
+++ b/include/mbedtls/mbedtls_config.h
@@ -1744,9 +1744,6 @@
  *
  * Enable support for RFC 8449 record_size_limit extension in SSL (TLS 1.3 only).
  *
- * \warning This extension is currently in development and must NOT be used except
- *          for testing purposes.
- *
  * Requires: MBEDTLS_SSL_PROTO_TLS1_3
  *
  * Uncomment this macro to enable support for the record_size_limit extension