quicapitest: Fix SSL_trace() test on big endian platforms

Reviewed-by: Hugo Landau <hlandau@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/21411)

include/internal/recordmethod.h

@@ -63,7 +63,7 @@ typedef struct ossl_record_layer_st OSSL_RECORD_LAYER;
  * buffer of payload data in |buf| of length |buflen|.
  */
 struct ossl_record_template_st {
-    int type;
+    unsigned char type;
     unsigned int version;
     const unsigned char *buf;
     size_t buflen;