Fix docker-pull remote operations build & push

[paladin-devops]

In version 0.8.2 of Waypoint, using remote operations with the docker-pull plugin exits without building the app. The error produced is indicated in this log message:

[DEBUG] waypoint.runner.agent.runner.app.example-nodejs.mapper.stdio: received EOF, stopping recv loop: job_id=01G4FSXDE0HJMNADYC94CWZ8AN job_op=*gen.Job_Build err="rpc error: code = Unavailable desc = error reading from server: read unix @->/kaniko/tmp/plugin25197406: read: connection reset by peer

This PR corrects that problem by updating the OCI registry that's created to align with the registry stanza details. The Docker context is now also explicitly provided to Kaniko.

#3394 has more details on the issue with remote operations. This is a gist of the build log and waypoint.hcl where I tested this out.

[vercel]

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Name	Status	Preview	Updated
waypoint-ui	✅ Ready (Inspect)	Visit Preview	Jun 6, 2022 at 3:58PM (UTC)

[briancain]

Minor comment from me! Otherwise looks pretty straight forward 😄

[briancain]

Code looks good to me! 👍🏻

[demophoon]

This looks good and remote building and pushing appear to work. However when testing this out it looks like we are still relying on docker for tagging images built with kaniko on remote runners.

✓ Running push build v2
❌ Tagging Docker image: registry-service/demophoon/nodejs-example:latest => registry-service/demophoon/nodejs-example:latest
! unable to tag image:Cannot connect to the Docker daemon at
  unix:///var/run/docker.sock. Is the docker daemon running?

I think this is automatically handled via kaniko when kaniko pushes the image to the registry so we might just need to skip that step for kaniko images.

[demophoon]