[core] `GetMouseDelta()` X and Y don't work correctly on web

[mandar1jn]

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Issue description

Looking at the source code, it is clear that platform web is not supported by the functions mentioned above. I noticed this while working on my gamejam project. I might create a pr tomorrow. Note that the problem is not the mouse, but when using touch. I get there are the GetTouchX and Y functions, but touch doesn't give an option for when touch is released. If this would be used as a counter argument, then there is no reason why GetMousePosition does work.

Environment

Building for the web

Issue Screenshot

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Code Example

Can't currently provide one

[raysan5]

@mandar1jn Are you sending a PR to solve this issue?

Maybe related issue: #2174