Kernel+AK: Eliminate a couple of temporary String allocations

Author: https://github.com/BertalanD
Commit: 1d2f78682b
Pull-request: https://github.com/SerenityOS/serenity/pull/11501

Kernel/Net/LocalSocket.cpp

@@ -378,7 +378,7 @@ ErrorOr<NonnullOwnPtr<KString>> LocalSocket::pseudo_path(const OpenFileDescripti
         break;
     }
 
-    return KString::try_create(builder.to_string());
+    return KString::try_create(builder.string_view());
 }
 
 ErrorOr<void> LocalSocket::getsockopt(OpenFileDescription& description, int level, int option, Userspace<void*> value, Userspace<socklen_t*> value_size)