Move delete keyboard shortcut in-progress gesture check to precondition

[BeksOmega]

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Describe the bug

The delete keyboard shortcut currently checks if there is a gesture in progress from within its callback function, and returns early if so. This is what the preconditionFn is meant to do. Other keyboard shortcuts check for in-progress gestures from there.

See the relevant code.

To Fix

1. Add a check to the precondition function to make sure a gesture is not in progress.
2. Remove the gesture check from the callback.

[SophieNguyen113]

I would love to work on this issue

[humera811]

@BeksOmega I am interested in working on this

[PrayagCodes]

I am interested
in these issue