fix: now discussion sidebar modal appears above the fold

[sundasnoreen12]

INF-1033

Description

One of our partner’s has shared the following:

”When I've been testing out the discussion sidebar, when trying to add an image or code the modal that pops up is not actually visible, and requires scrolling to reach it. The post UI fades out like this with no indication that there's anything below it:

You then have to scroll down quite far to be able to add your image/code

Now for learning discussion side i fixed this issue by change the modal position from align center to align start.

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