Cascade delete interaction step

[crayolakat]

Fixes ProgressiveCoders#1673

Description

Currently, we are unable to delete interaction steps with children. The solution is to change the foreign key constraint of parent_interaction_id in the interaction_step table to cascade delete.

Checklist:

• I have manually tested my changes on desktop and mobile
• The test suite passes locally with my changes
• If my change is a UI change, I have attached a screenshot to the description section of this pull request
• My change is 300 lines of code or less, or has a documented reason in the description why it’s longer
• I have made any necessary changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• My PR is labeled [WIP] if it is in progress

[crayolakat]

Interaction steps of campaigns that have already started are unable to be deleted, so I changed the test to use a campaign that hasn't started yet.

[crayolakat]

This branch was previously approved and merged into the now inactive community-branches-qa branch, and has been successfully running on MoveOn's prod website for months.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues

Measures
0 Security Hotspots
No data about Coverage
1.5% Duplication on New Code

See analysis details on SonarCloud