Include missing stdint.h on fuzz test (#1700)

* Include missing stdint.h

* Remove std:: from uint8_t

test/fuzzing/server_fuzzer.cc

@@ -1,5 +1,6 @@
+#include <cstdint>
+
 #include <httplib.h>
-#include <memory>
 
 class FuzzedStream : public httplib::Stream {
 public:

test/fuzzing/standalone_fuzz_target_runner.cpp

@@ -5,9 +5,9 @@
 // on the test corpus or on a single file,
 // e.g. the one that comes from a bug report.
 
-#include <cassert>
-#include <iostream>
+#include <cstdint>
 #include <fstream>
+#include <iostream>
 #include <vector>
 
 // Forward declare the "fuzz target" interface.