Bugfix/multiple bug fixes for modals

[hannyle]

Description

• Fixing bugs related to modals' size and the background page's scrolling effect when opening/closing modals.
• Copy modal will now have a pre-filled foldername as copy from the original foldername. For example: Original foldername is Folder ABC, the pre-filled copy foldername will be Folder ABC copy 1.

Related issues

Fixes #798, #799, #812, #813, #817, #823,

Type of change

• Bug fix (non-breaking change which fixes an issue)

Changes Made

• Created a function to check and convert the current foldername to a copy foldername in the form of foldername + "copy" + "version". The version increments every time we create a new copy of the same foldername.
• Checking if folder already exists in Copy modal will only fire when user starts modifying the foldername
• Updated Changelog

Testing

• Tests do not apply

Mentions

[sampsapenna]

LGTM 👍🏼