build(Makefile): add support for building container images for current-context cluster with ttl.sh registry and 24h TTL

[kaovilai]

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Fixes #(issue)

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• [ ] Accepted the DCO. Commits without the DCO will delay acceptance.
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[kaovilai]

/kind changelog-not-required

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 58.99%. Comparing base (aab2140) to head (60aece1). Report is 36 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #8319 +/- ## ========================================== - Coverage 59.21% 58.99% -0.22% ========================================== Files 367 367 Lines 30841 38847 +8006 ========================================== + Hits 18262 22918 +4656 - Misses 11119 14467 +3348 - Partials 1460 1462 +2 ```

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[blackpiglet]

Could you give more information about the ttl.sh registry?

[kaovilai]

ttl.sh Contributed by Replicated Anonymous & ephemeral Docker image registry

Free to use. No need to sign-up. Open source.

How to use ttl.sh

1. Tag your image with ttl.sh, a UUID, & time limit (i.e. :2h)

2. Push your image

3. Pull your image (before it expires)

[kaovilai]

Follow up enhancements may add a target like so

install-current-context: container-current-context
    go run cmd/velero/velero.go install --image=<image-from-this-pr-target> --provider aws --bucket $AWS_BUCKET --prefix velero --plugins velero/velero-plugin-for-aws:latest --secret-file $AWS_SECRET_FILE

[kaovilai]

the advantage is user who clone this repo do not need to docker login someregistry.io or create a repository to push to.

[blackpiglet]

IMO, this change is making developing more convenient, but the ttl.sh is not a registry that can host the images for a long time, and I'm not sure whether ttl.sh is available for most environments, for example, I'm blocked from it by the firewall.

As a result, I suggest to keep this change as private.

[kaovilai]

ack. you can always use your own registry and override with if that's preferable. or this can be modified to require your own registry. If that's desirable lmk. Closing for now.