fix a flaky test (#57)

Co-authored-by: Ghous Amjad <gamjad@google.com>

.bazelrc

diff --git a/.bazelrc b/.bazelrc
index 851c1c9..f73889e 100644
--- a/.bazelrc
+++ b/.bazelrc
@@ -6,4 +6,4 @@
 build --java_language_version=21
 build --tool_java_language_version=21
 build --java_runtime_version=remotejdk_21
-build --tool_java_runtime_version=remotejdk_21
+build --tool_java_runtime_version=remotejdk_21
\ No newline at end of file

anonymous_tokens/cpp/client/anonymous_tokens_rsa_bssa_client_test.cc

diff --git a/anonymous_tokens/cpp/client/anonymous_tokens_rsa_bssa_client_test.cc b/anonymous_tokens/cpp/client/anonymous_tokens_rsa_bssa_client_test.cc
index 25aa7a8..e0c8f94 100644
--- a/anonymous_tokens/cpp/client/anonymous_tokens_rsa_bssa_client_test.cc
+++ b/anonymous_tokens/cpp/client/anonymous_tokens_rsa_bssa_client_test.cc
@@ -549,7 +549,7 @@
   // corrupt the tokens
   for (auto& token : tokens) {
     std::string token_bytes = token.token().token();
-    token_bytes[50] = 'a';
+    token_bytes[50] ^= 0xFF;
     token.mutable_token()->set_token(token_bytes);
   }
   RunVerifier(tokens, public_key_, /*expected_verification_success=*/false);