Fix incorrect setup instructions in The profiler

[Calinou]

• This closes Profiler documentation suggests the profiler should be started before running the game, rather than after the game is running #9902.

[clayjohn]

Looks good. I just checked and the old language was true for Godot 3.5.3. So we might want to see why the behaviour changed and consider bringing back the ability to start the profiler before running the game

[skyace65]

Thanks!

[Calinou]

Looks good. I just checked and the old language was true for Godot 3.5.3. So we might want to see why the behaviour changed and consider bringing back the ability to start the profiler before running the game

This was changed by godotengine/godot#70151. See also godotengine/godot#72524.

[mhilbrunner]

Cherry-picked to 4.3 in #10038.