fuzz: replace every fuzzer-controlled loop with a LIMITED_WHILE loop

Blindly chose a cap of 10000 iterations for every loop, except for
the two in script_ops.cpp and scriptnum_ops.cpp which appeared to
(sometimes) be deserializing individual bytes; capped those to one
million to ensure that sometimes we try working with massive scripts.

There was also one fuzzer-controlled loop in timedata.cpp which was
already capped, so I left that alone.

git grep 'while (fuzz' should now run clean except for timedata.cpp

src/test/fuzz/crypto_chacha20.cpp

@@ -19,7 +19,7 @@ FUZZ_TARGET(crypto_chacha20)
         const std::vector<unsigned char> key = ConsumeFixedLengthByteVector(fuzzed_data_provider, fuzzed_data_provider.ConsumeIntegralInRange<size_t>(16, 32));
         chacha20 = ChaCha20{key.data(), key.size()};
     }
-    while (fuzzed_data_provider.ConsumeBool()) {
+    LIMITED_WHILE(fuzzed_data_provider.ConsumeBool(), 10000) {
         CallOneOf(
             fuzzed_data_provider,
             [&] {