VFB-201: Remove new packing slot from table if error on creation

What's changed

If there is an error when creating a new packing slot, the new row now disappears.

When adding "test" slot. Now is not shown once the error has occurred.	Before	After

[x] The ticket is up-to-date - Please document any deviations from the original approach if there is any.
[x] I have documented the testing steps for QA
[x] I have self-reviewed this PR
[x] Make sure you've verified it works via npm run dev
[x] Make sure you've verified it works via npm run build and npm run start
[x] Make sure you've fixed all linting problems with npm run lint_fix
[x] Make sure you've tested via npm run test:e2e