LibDebug: Move everything into the "Debug" namespace

Author: https://github.com/Lubrsi
Commit: 694b86a4bf
Pull-request: https://github.com/SerenityOS/serenity/pull/3290

Libraries/LibDebug/DebugSession.h

@@ -42,6 +42,8 @@
 #include <sys/wait.h>
 #include <unistd.h>
 
+namespace Debug {
+
 class DebugSession {
 public:
     static OwnPtr<DebugSession> exec_and_attach(const String& command);
@@ -243,3 +245,5 @@ void DebugSession::run(Callback callback)
         }
     }
 }
+
+}