Add test for default deadLetterSink namespace in generic Channel

[pierDipi]

See #5906 (review)

Fixes #5906 (review)

Proposed Changes

• Add test for default deadLetterSink namespace in generic Channel

Pre-review Checklist

• At least 80% unit test coverage
• E2E tests for any new behavior
• Docs PR for any user-facing impact
• Spec PR for any new API feature
• Conformance test for any change to the spec

Release Note

None

Docs

None

/assign @odacremolbap

[codecov]

Codecov Report

Merging #5908 (29b44fe) into main (1e9f9f1) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #5908   +/-   ##
=======================================
  Coverage   82.02%   82.02%           
=======================================
  Files         220      220           
  Lines        7527     7527           
=======================================
  Hits         6174     6174           
  Misses        918      918           
  Partials      435      435           

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 1e9f9f1...29b44fe. Read the comment docs.

[knative-prow-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: odacremolbap, pierDipi

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Details

Needs approval from an approver in each of these files:

• OWNERS [pierDipi]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment