throw error if datasource not found

[edwardmedia]

Fixes hashicorp/terraform-provider-google#12850

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Release Note Template for Downstream PRs (will be copied)

container: throw exception if the data source `google_container_cluster` does not exist

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[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

Terraform GA: Diff ( 1 file changed, 14 insertions(+), 2 deletions(-))
Terraform Beta: Diff ( 1 file changed, 14 insertions(+), 2 deletions(-))
TF Validator: Diff ( 2 files changed, 3 insertions(+), 3 deletions(-))

[modular-magician]

Tests analytics

Total tests: 2216
Passed tests 1976
Skipped tests: 239
Failed tests: 1

Action taken

Triggering VCR tests in RECORDING mode for the tests that failed during VCR. Click here to see the failed tests

TestAccFirebaserulesRelease_BasicRelease

[modular-magician]

Tests passed during RECORDING mode:
TestAccFirebaserulesRelease_BasicRelease[Debug log]

All tests passed
View the build log or the debug log for each test