Chat edit function

[JayaBadarawada]

• Creating edit functionality for the post.
• Writing the edit function for the backend.
• This edit function is only visible to the user who posted that post.
• Comments only have a delete option, this delete option should be visible to both the user who commented and the super admin.
• When the user presses the edit button, it opens the AddOrEditPost screen, where the user can able to change the description and image. After pressing save, an alert will confirm the changes.
• If the user makes some changes and saves the post, it shows the text "ändrats" on the post.
• Adding ChatCardEditMenu to ChatCardScreen so that users can delete their own posts there as well.
• Adding the same edit functionality to MessageCard.
• Adapting tests in ChatCard.