Update generated cloudbuild trigger tests use sweepable name

[SarahFrench]

I saw this error for the TestAccCloudBuildTrigger_cloudbuildTriggerAllowExitCodesExample acceptance test:

Error: Error creating Trigger: googleapi: Error 409: trigger (594424405950, trigger) already exists

I checked, and found acc tests that don't set the name field, as it's optional. To ensure that these resources are made in a sweepable way with unique names I'm making the tests include the optional name argument.

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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 providers, and ran make test and make lint in the generated providers to ensure it passes unit and linter tests.
• Ran relevant acceptance tests using my own Google Cloud project and credentials (If the acceptance tests do not yet pass or you are unable to run them, please let your reviewer know).
• Read Write release notes before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

[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 ( 2 files changed, 6 insertions(+))
Terraform Beta: Diff ( 2 files changed, 6 insertions(+))
TF OiCS: Diff ( 3 files changed, 3 insertions(+))

[modular-magician]

Tests analytics

Total tests: 2960
Passed tests 2655
Skipped tests: 302
Affected tests: 3

Action taken

Found 3 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccCloudBuildTrigger_cloudbuildTriggerAllowFailureExample|TestAccCloudBuildTrigger_cloudbuildTriggerBuildExample|TestAccCloudBuildTrigger_cloudbuildTriggerAllowExitCodesExample

Get to know how VCR tests work

[modular-magician]

$\textcolor{green}{\textsf{Tests passed during RECORDING mode:}}$
TestAccCloudBuildTrigger_cloudbuildTriggerAllowFailureExample[Debug log]
TestAccCloudBuildTrigger_cloudbuildTriggerBuildExample[Debug log]
TestAccCloudBuildTrigger_cloudbuildTriggerAllowExitCodesExample[Debug log]

Rerun these tests in REPLAYING mode to catch issues

$\textcolor{green}{\textsf{No issues found for passed tests after REPLAYING rerun.}}$

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$\textcolor{green}{\textsf{All tests passed!}}$
View the build log or the debug log for each test