refactor: Fix remaining clang-tidy performance-inefficient-vector errors

src/rpc/output_script.cpp

@@ -123,6 +123,7 @@ static RPCHelpMan createmultisig()
             // Get the public keys
             const UniValue& keys = request.params[1].get_array();
             std::vector<CPubKey> pubkeys;
+            pubkeys.reserve(keys.size());
             for (unsigned int i = 0; i < keys.size(); ++i) {
                 pubkeys.push_back(HexToPubKey(keys[i].get_str()));
             }

src/test/checkqueue_tests.cpp

@@ -360,6 +360,7 @@ BOOST_AUTO_TEST_CASE(test_CheckQueueControl_Locks)
     auto queue = std::make_unique<Standard_Queue>(QUEUE_BATCH_SIZE, SCRIPT_CHECK_THREADS);
     {
         std::vector<std::thread> tg;
+        tg.reserve(3);
         std::atomic<int> nThreads {0};
         std::atomic<int> fails {0};
         for (size_t i = 0; i < 3; ++i) {

src/test/cuckoocache_tests.cpp

@@ -224,6 +224,7 @@ void test_cache_erase_parallel(size_t megabytes)
     /** Spin up 3 threads to run contains with erase.
      */
     std::vector<std::thread> threads;
+    threads.reserve(3);
     /** Erase the first quarter */
     for (uint32_t x = 0; x < 3; ++x)
         /** Each thread is emplaced with x copy-by-value

src/test/rpc_tests.cpp

@@ -428,6 +428,7 @@ BOOST_AUTO_TEST_CASE(rpc_getblockstats_calculate_percentiles_by_weight)
 {
     int64_t total_weight = 200;
     std::vector<std::pair<CAmount, int64_t>> feerates;
+    feerates.reserve(200);
     CAmount result[NUM_GETBLOCKSTATS_PERCENTILES] = { 0 };
 
     for (int64_t i = 0; i < 100; i++) {