We should use Delete modal instead of alert pop up and also add toasts messages on delete activity

[MahtabBukhari]

Describe the bug
When we delete an activity then there is window alert popup is used for confirmation
We should have to use the project delete confirmation modal instead

To Reproduce
Steps to reproduce the behavior:

1. Go to 'Activity page'
2. Click on 'on Delete button'
3. See error

Expected behavior
We should have to use delete confirmation modal of the project instead of window alert pop up for confirmation

https://www.loom.com/share/127364baec1b421fb371427b1181c649?sid=721a5c9a-ebcd-4e36-8dbb-cf7e3122d241

Acceptance Criteria

• I have tested on Chrome desktop
• I have posted a screenshot or video in my PR
• I have rebased and tested locally before submitting my PR
• I can submit a PR within 2 days of taking the bounty

[MahtabBukhari]

@tomsmith8 @Edvardoh @Evanfeenstra Could you please review the issue and assign to me?