An attempt to fix the "double click" bug on MacOS

[eriksvedang]

Here's my attempt at solving the bug described here not-fl3/macroquad#422

The way to reliably (100%) reproduce the bug on MacOS is to launch the program from the command line, and constantly move the cursor around the screen while the program is starting (adding a call to sleep at the beginning of the program makes this easier to perform).

This PR uses the method call [[NSRunningApplication currentApplication] activateWithOptions] which is documented here: https://developer.apple.com/documentation/appkit/nsrunningapplication/1528725-activatewithoptions

In my testing, the game window is still inactive (gray) after this code has been called, but the double click bug described in the original issue is gone after clicking the window once. That the window actually doesn't get active (which one would assume...) implies that there's more room for improvement here, since the method call actually doesn't make the window active. But the user experience with this fix is at least a lot better than the current behaviour.

If this fix is good enough and we want to merge it in, I'd need some help to decide where the best place to actually call prevent_double_click_bug_on_macos function from (right now I manually call it in my test program).

[birhburh]

Oh, so it was a bug, and not me constantly misclicking.