[Mobile] Art Item Auction

[atillaturkmen]

I was assigned to implement the art item auction support to our app in our group meeting during this week's lab session.

These are the tasks to complete this issue:

• [x] Create a new branch.
• [x] Add a button for starting an auction that is only visible to the owner of the art item.
• [x] Other users will be able to make bids for the art item.
• [x] Artist will be able to stop the auction.

Deadline: 27/12/2022 11:00 Reviewer: @canatakan

[atillaturkmen]

All of the tasks are complete. Here are example screenshots:

Now I will open a pull request and add @canatakan as the reviewer.

[canatakan]

• I approved and merged your pull request #620.
• Please check my review for a feature request

Currently, the task is completed and the issue can be closed.