test: suppress compiler warning in test_bigint

Currently the are two of following compiler warnings is
generated:

In file included from ../test_bigint.c:5:
../test_bigint.c: In function ‘CreateTooBigBigInt’:
../test_bigint.c:120:22: warning:
‘words’ may be used uninitialized [-Wmaybe-uninitialized]

This commit initialized the words array to avoid these warnings.

PR-URL: #40253
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>

test/js-native-api/test_bigint/test_bigint.c

@@ -113,7 +113,7 @@ static napi_value TestWords(napi_env env, napi_callback_info info) {
 static napi_value CreateTooBigBigInt(napi_env env, napi_callback_info info) {
   int sign_bit = 0;
   size_t word_count = SIZE_MAX;
-  uint64_t words[10];
+  uint64_t words[10] = {0};
 
   napi_value output;
 
@@ -125,7 +125,7 @@ static napi_value CreateTooBigBigInt(napi_env env, napi_callback_info info) {
 
 // Test that we correctly forward exceptions from the engine.
 static napi_value MakeBigIntWordsThrow(napi_env env, napi_callback_info info) {
-  uint64_t words[10];
+  uint64_t words[10] = {0};
   napi_value output;
 
   napi_status status = napi_create_bigint_words(env,