Remove Rendertron usage since it is deprecated

[ramrodo]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

This PRs removes Rendertron since it is deprecated.

With this removal, the krel testgridshot tool will no longer take screenshots of the TestGrid boards at adding the GitHub comment to the release cut issue. Also, it will no longer upload any screenshot to the GCS bucket.

We need this removal since every time we run krel testgridshot and it tries to get the screenshot, the process fails and does not publish any GitHub comment throwing this error:

$ krel testgridshot
INFO Starting krel testgrishot...                 
INFO Sending GET request to https://testgrid.k8s.io/sig-release-master-blocking/summary 
INFO Sending GET request to https://testgrid.k8s.io/sig-release-master-informing/summary 
INFO rendertronURL for https://testgrid.k8s.io/sig-release-master-informing#gce-master-scale-performance&width=30: https://render-tron.appspot.com/screenshot/https:%2F%2Ftestgrid.k8s.io%2Fsig-release-master-informing%23gce-master-scale-performance&width=30?width=3000&height=2500 
INFO Sending GET request to https://render-tron.appspot.com/screenshot/https:%2F%2Ftestgrid.k8s.io%2Fsig-release-master-informing%23gce-master-scale-performance&width=30?width=3000&height=2500 
FATA processing the dashboards: failed to get the testgrid screenshot: HTTP error 404 Not Found for https://render-tron.appspot.com/screenshot/https:%2F%2Ftestgrid.k8s.io%2Fsig-release-master-informing%23gce-master-scale-performance&width=30?width=3000&height=2500

This error has been mentioned a couple of times before at least, see:

• #issuecomment-1189229139
• #issuecomment-1298967991

Which issue(s) this PR fixes:

None

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

[ramrodo]

/cc @cici37 @gracenng

[cici37]

Thanks for the PR!
/lgtm

[cici37]

/assign @cpanato @puerco
for approval if you have time? Thank you

[saschagrunert]

Do we have an alternative to rendertron?

[ramrodo]

Do we have an alternative to rendertron?

Good question @saschagrunert. I could not find a free and reliable tool to take screenshots online (without installing other dependencies). I found this screenshotmachine site that allows us to take 100 screenshots free per month but we need to create an account to get a token. Not sure if we have an org account for these types of services.

[cici37]

I plan to update the doc and issue template to let people manually add testgrid status as of now before a replacement is in place. This PR at least will help in terms of generating testgrid status without throwing errors. Maybe the issue for finding/applying replacement of Rendertron?

[palnabarun]

We can continue exploring #2783 by @xmudrii to replace rendertron.

[xmudrii]

I've been a bit busy with work and KEP-1731, but I'm happy to pick this up again in near future. There are some things that I need to fix in #2783 but in general it works pretty well.

[cici37]

Thanks for sharing! I have closed the issue since the work is planned and ongoing :)

[saschagrunert]

Let's move forward with this one and let #2783 provide a future replacement.

[palnabarun]

/approve

[palnabarun]

/priority critical-urgent

[cpanato]

agree
/approve
/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cpanato, palnabarun, ramrodo, saschagrunert

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