gravity: remove the unused ?go code

[XhmikosR]

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[yubiuser]

You're correct, this is currently unused. I wonder if we should use it?

[XhmikosR]

I don't really remember where it was linked from on v5 TBH. Also, I don't think it's a big deal if the user has to click update themselves, but we can bring back the old behavior if you guys prefer that (assuming we find where it was linked from).

[rdwebdesign]

The ?go option was used in Settings page to automatically start Gravity update:

web/settings.php

Lines 40 to 49 in be05b0f

	<?php // Check if ad lists should be updated after saving ...
	if (isset($_POST['submit'])) {
	if ($_POST['submit'] == 'saveupdate') {
	// If that is the case -> refresh to the gravity page and start updating immediately
	?>
	<meta http-equiv="refresh" content="1;url=gravity.php?go">
	<?php
	}
	}
	?>

But apparently the button used to trigger this option was removed a long time ago by this commit.

[yubiuser]

I think this can go for now. Can be re-added later if necessary.