Fix .docker/config.json path

[julianxhokaxhiu]

Fixes #1455 as well as many others that can be found here: https://github.com/GoogleContainerTools/kaniko/issues?q=is%3Aissue+is%3Aopen+ecr+push

Description

Apparently in the overall documentation it's stated to put the docker config.json inside of /kaniko/.docker but kaniko seems to request the file in /root/.docker which makes sense as the container uses UID 0 ( when running whoami ). Therefore, update the path in the documentation.

Submitter Checklist

N/A - Documentation

Reviewer Notes

N/A - Documentation

Release Notes

N/A - Documentation

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[julianxhokaxhiu]

@googlebot I signed it!

[julianxhokaxhiu]

Apparently without even touching the .docker/config.json kaniko is able to push to ECR anyway, just having the right AWS config file in the right path /root/.aws/config is enough.

Closing the PR.