Redirect and toasts for withdrawn collections and datasets (CXG) were regressed

[brianraymor]

Context

See the original design:

• Curators may delete a published collection
• feat(withdraw): Add withdrawn collection toasts
• feat(withdraw): Add withdrawn dataset toast

Refinements

A withdrawn collection should now redirect the consumer to the collections tab. The related message:

      "This collection was withdrawn. You’ve been redirected to the cellxgene Data Portal homepage.",

needs to be updated:

      "This collection was withdrawn. You’ve been redirected to Collections.",

[MillenniumFalconMechanic]

See Slack.

What I did:

• Deleted a collection
• Viewed the deleted collection in the DP

What happened:

• Redirected to the DP home page

What I expected:

• Redirected to the collections tab
• Toast popped with the updated text (as above)