Add conflictswith on autopilot to node config

[slevenick]

Fixes: hashicorp/terraform-provider-google#8863

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• Searched through the issue tracker for an open issue that this either resolves or contributes to, commented on it to claim it, and written "fixes {url}" or "part of {url}" in this PR description. If there were no relevant open issues, I opened one and commented that I would like to work on it (not necessary for very small changes).
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Release Note Template for Downstream PRs (will be copied)

container: fixed a bug that allowed specifying `node_config` on `google_container_cluster` when autopilot is used

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 1 file changed, 2 insertions(+))
Terraform Beta: Diff ( 2 files changed, 3 insertions(+), 2 deletions(-))

[modular-magician]

I have triggered VCR tests based on this PR's diffs. See the results here: "https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=181271"

[modular-magician]

I have triggered VCR tests in RECORDING mode for the following tests that failed during VCR: TestAccCloudRunDomainMapping_foregroundDeletion|TestAccDataprocCluster_withConfigOverrides You can view the result here: "https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=181277"

[modular-magician]

Tests failed during RECORDING mode: TestAccDataprocCluster_withConfigOverrides|TestAccCloudRunDomainMapping_foregroundDeletion Please fix these to complete your PR

[c2thorn]

Shouldn't be a breaking change, as node_configs+enable_autopilot leaves a permadiff anyway