drop manual use of knative.dev/pkg::injection.Dynamic

[dprotaso]

Changes

Fixes: https://github.com/tektoncd/triggers/issues/1593

Upstream Knative is maintaining some codegen to faciliate a k8s dynamic.Client being the underlying implementation of a kubernetes.Interface

It turns out it doesn't really have any usage except for this repo.

We're looking to remove this functionality - (discussion https://github.com/knative/pkg/issues/2739#issuecomment-1550452957)

Submitter Checklist

As the author of this PR, please check off the items in this checklist:

• [ ] Has Docs if any changes are user facing, including updates to minimum requirements e.g. Kubernetes version bumps
• [ ] Has Tests included if any functionality added or changed
• [ ] Follows the commit message standard
• [ ] Meets the Tekton contributor standards (including functionality, content, code)
• [ ] Has a kind label. You can add one by adding a comment on this PR that contains /kind <type>. Valid types are bug, cleanup, design, documentation, feature, flake, misc, question, tep
• [ ] Release notes block below has been updated with any user facing changes (API changes, bug fixes, changes requiring upgrade notices or deprecation warnings). See some examples of good release notes.
• [ ] Release notes contains the string "action required" if the change requires additional action from users switching to the new release

Release Notes

NONE

[tekton-robot]

Hi @dprotaso. Thanks for your PR.

I'm waiting for a tektoncd member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[imjasonh]

/ok-to-test

[tekton-robot]

The following is the coverage report on the affected files. Say /test pull-tekton-triggers-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/reconciler/metrics/injection.go	45.5%	44.4%	-1.0
pkg/sink/cloudevent/cloudeventclient.go	11.1%	5.9%	-5.2

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dibyom

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[dibyom]

/cc @khrm @savitaashture

[savitaashture]

/lgtm

:+1: