fuzz: Avoid time-based "non-determinism" in fuzzing harnesses by using mocked GetTime()

src/test/fuzz/banman.cpp

@@ -32,6 +32,7 @@ void initialize()
 void test_one_input(const std::vector<uint8_t>& buffer)
 {
     FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
+    SetMockTime(ConsumeTime(fuzzed_data_provider));
     const fs::path banlist_file = GetDataDir() / "fuzzed_banlist.dat";
     fs::remove(banlist_file);
     {

src/test/fuzz/connman.cpp

@@ -23,6 +23,7 @@ void initialize()
 void test_one_input(const std::vector<uint8_t>& buffer)
 {
     FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
+    SetMockTime(ConsumeTime(fuzzed_data_provider));
     CConnman connman{fuzzed_data_provider.ConsumeIntegral<uint64_t>(), fuzzed_data_provider.ConsumeIntegral<uint64_t>(), fuzzed_data_provider.ConsumeBool()};
     CAddress random_address;
     CNetAddr random_netaddr;

src/test/fuzz/net.cpp

@@ -27,7 +27,7 @@ void initialize()
 void test_one_input(const std::vector<uint8_t>& buffer)
 {
     FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
-
+    SetMockTime(ConsumeTime(fuzzed_data_provider));
     const std::optional<CAddress> address = ConsumeDeserializable<CAddress>(fuzzed_data_provider);
     if (!address) {
         return;

src/test/fuzz/rbf.cpp

@@ -18,6 +18,7 @@
 void test_one_input(const std::vector<uint8_t>& buffer)
 {
     FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
+    SetMockTime(ConsumeTime(fuzzed_data_provider));
     std::optional<CMutableTransaction> mtx = ConsumeDeserializable<CMutableTransaction>(fuzzed_data_provider);
     if (!mtx) {
         return;