refactor: FleetAutoscaler Validate use field.ErrorList

[aimuz]

Signed-off-by: aimuz mr.imuz@gmail.com

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

/kind breaking
/kind cleanup

What this PR does / Why we need it:

Which issue(s) this PR fixes:

Closes #

Special notes for your reviewer:

[agones-bot]

Build Succeeded 👏

Build Id: d1342437-1a94-417b-8210-6504a1d1b2e9

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:1.34.0-dev-47bf168-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-extensions:1.34.0-dev-47bf168-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-sdk:1.34.0-dev-47bf168-linux-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-ping:1.34.0-dev-47bf168-amd64
• image: us-docker.pkg.dev/agones-images/ci/agones-allocator:1.34.0-dev-47bf168-amd64
• Linux C++ SDK (build): agonessdk-1.34.0-dev-47bf168-amd64-linux-arch_64.tar.gz
• SDK Server: agonessdk-server-1.34.0-dev-47bf168-amd64.zip

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

• https://47bf168-dot-preview-dot-agones-images.appspot.com/

To install this version:

• git fetch https://github.com/googleforgames/agones.git pull/3272/head:pr_3272 && git checkout pr_3272
• helm install agones ./install/helm/agones --namespace agones-system --set agones.image.registry=us-docker.pkg.dev/agones-images/ci --set agones.image.tag=1.34.0-dev-47bf168-amd64

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aimuz, markmandel

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• OWNERS [markmandel]

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