Add notificationPubsubTopic to BigQuery Data Transfer

[14kw]

If this PR is for Terraform, I acknowledge that I have:

• 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).
• Generated Terraform, and ran make test and make lint to ensure it passes unit and linter tests.
• Ensured that all new fields I added that can be set by a user appear in at least one example (for generated resources) or third_party test (for handwritten resources or update tests).
• Ran relevant acceptance tests (If the acceptance tests do not yet pass or you are unable to run them, please let your reviewer know).
• Read the Release Notes Guide before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

bigquery: added `notification_pubsub_topic` field to `google_bigquery_data_transfer_config` resource

part of hashicorp/terraform-provider-google#5866

[modular-magician]

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@danawillow, please review this PR or find an appropriate assignee.

[modular-magician]

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

Diff report:

Terraform GA: Diff ( 3 files changed, 43 insertions(+))
Terraform Beta: Diff ( 3 files changed, 43 insertions(+))
TF Conversion: Diff ( 1 file changed, 10 insertions(+))

[danawillow]

LGTM, thanks @14kw!

[danawillow]

Oh sorry, had one quick comment.

[danawillow]

Can this be given a name with randomness like we do for the dataset? That'll make sure separate test runs don't conflict. Also starting it with tf-test is a good practice because we have some automation that cleans up resources in our test environment with that prefix.

[modular-magician]

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

Diff report:

Terraform GA: Diff ( 3 files changed, 44 insertions(+), 1 deletion(-))
Terraform Beta: Diff ( 3 files changed, 44 insertions(+), 1 deletion(-))
TF Conversion: Diff ( 1 file changed, 10 insertions(+))