added local as default for registry when registry is not specified

[kamaljeeti]

What type of PR is this?

Uncomment only one /kind <> line, press enter to put that in a new line, and remove leading whitespace from that line:

/kind breaking

/kind bug

/kind cleanup
/kind documentation
/kind feature
/kind hotfix
/kind release

What this PR does / Why we need it:

Which issue(s) this PR fixes:#3859

Closes #3859

Special notes for your reviewer:

[agones-bot]

Build Succeeded 👏

Build Id: 67130794-beb8-417a-8e5a-ad65c2a39fae

The following development artifacts have been built, and will exist for the next 30 days:

• image: us-docker.pkg.dev/agones-images/ci/agones-controller:1.42.0-dev-caa280d-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-extensions:1.42.0-dev-caa280d-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-sdk:1.42.0-dev-caa280d-linux-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-ping:1.42.0-dev-caa280d-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-allocator:1.42.0-dev-caa280d-amd64
• Linux C++ SDK (build): agonessdk-1.42.0-dev-caa280d-amd64-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.42.0-dev-caa280d-amd64.zip

A preview of the website (the last 30 builds are retained):

• https://caa280d-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/3876/head:pr_3876 && git checkout pr_3876
• helm install agones ./install/helm/agones --namespace agones-system --set agones.image.registry=us-docker.pkg.dev/agones-images/ci --set agones.image.tag=1.42.0-dev-caa280d-amd64

[igooch]

Is this working on your machine? When I run make build-images I still run into the same error message as the original issue

me@me:~/agones/build$ make build-images
...
ERROR: invalid tag "/agones-controller:1.42.0-dev-caa280d-amd64": invalid reference format
make: *** [Makefile:529: build-controller-image-amd64] Error 1

Edit: Nevermind the above comment, this does work. I just needed to run unset REGISTRY.

[igooch]

LGTM

[agones-bot]

Build Succeeded 👏

Build Id: dd695cee-9251-439d-ac28-31dfb4628c0b

The following development artifacts have been built, and will exist for the next 30 days:

• image: us-docker.pkg.dev/agones-images/ci/agones-controller:1.42.0-dev-8603011-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-extensions:1.42.0-dev-8603011-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-sdk:1.42.0-dev-8603011-linux-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-ping:1.42.0-dev-8603011-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-allocator:1.42.0-dev-8603011-amd64
• Linux C++ SDK (build): agonessdk-1.42.0-dev-8603011-amd64-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.42.0-dev-8603011-amd64.zip

A preview of the website (the last 30 builds are retained):

• https://8603011-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/3876/head:pr_3876 && git checkout pr_3876
• helm install agones ./install/helm/agones --namespace agones-system --set agones.image.registry=us-docker.pkg.dev/agones-images/ci --set agones.image.tag=1.42.0-dev-8603011-amd64