feat: Create sample for routeoptimization

[bshi]

Description

Note: Before submitting a pull request, please open an issue for discussion if you are not associated with Google.

Checklist

• [X] I have followed Sample Guidelines from AUTHORING_GUIDE.MD
• [X] README is updated to include all relevant information
• [x] Tests pass: nox -s py-3.9 (see Test Environment Setup)
• [x] Lint pass: nox -s lint (see Test Environment Setup)
• [X] These samples need a new API enabled in testing projects to pass (let us know which ones) routeoptimization.googleapis.com
• [ ] These samples need a new/updated env vars in testing projects set to pass (let us know which ones)
• [x] This sample adds a new sample directory, and I updated the CODEOWNERS file with the codeowners for this sample
• [x] This sample adds a new Product API, and I updated the Blunderbuss issue/PR auto-assigner with the codeowners for this sample
• [x] Please merge this PR for me once it is approved

[snippet-bot[bot]]

Here is the summary of changes.

You are about to add 1 region tag.

• routeoptimization/snippets/optimize_tours.py:15, tag routeoptimization_optimize_tours_basic

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[bshi]

Tests blocked by API enablement (or enablement propagation)

[davidcavazos]

Enabled the api in the testing project, re-running tests.

[davidcavazos]

  File "/workspace/routeoptimization/snippets/optimize_tours_test.py", line 26, in test_call_sync_api
    for val in (got.routes, got.visits, got.metrics):
                            ^^^^^^^^^^
  File "/workspace/routeoptimization/snippets/.nox/py-3-12/lib/python3.12/site-packages/proto/message.py", line 906, in __getattr__
    raise AttributeError(
AttributeError: Unknown field for OptimizeToursResponse: visits

Looks like that field doesn't exist?

[bshi]

@davidcavazos I apologize for the delay. Addressed your comments.

[glasnt]

Since this PR was created, we're introduced Python 3.13 testing. Please rebase this PR to ensure this check passes (if this API doesn't yet support Python 3.13, please update the noxfile to ignore this version)

[glasnt]

Hi! You haven't replied to this PR in 6 months; it looks like this change is no longer a priority for you.

If this PR has been closed in error, please re-open and address previous review comments ✨