Libraries: Use default constructors/destructors in LibGemini

https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#cother-other-default-operation-rules

"The compiler is more likely to get the default semantics right and
you cannot implement these functions better than the compiler."

Userland/Libraries/LibGemini/Job.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, the SerenityOS developers.
+ * Copyright (c) 2020-2022, the SerenityOS developers.
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -18,10 +18,6 @@ Job::Job(const GeminiRequest& request, Core::Stream::Stream& output_stream)
 {
 }
 
-Job::~Job()
-{
-}
-
 void Job::start(Core::Stream::Socket& socket)
 {
     VERIFY(!m_socket);