Fix example test names to comply with Go 1.24 vet checks

[rauchy]

What changes are proposed in this pull request?

This PR updates the names of many Example... functions in *_usage_test.go files across multiple service packages to comply with stricter vet rules introduced in Go 1.24.

• WHAT: Renamed example functions so that their names match real exported identifiers.
• WHY: In Go 1.24, the tests analyzer in go vet enforces that example function names must map to valid exported identifiers. These stricter checks caused previously valid tests to fail during go test, even though the actual test logic remained unchanged.

How is this tested?

Validated by running make test locally with Go 1.24. All example tests now pass without build or vet errors.

NO_CHANGELOG=true

[parthban-db]

Can we start running our unit tests in go1.24?

[github-actions]

If integration tests don't run automatically, an authorized user can run them manually by following the instructions below:

Trigger:
go/deco-tests-run/sdk-go

Inputs:

• PR number: 1203
• Commit SHA: 6c9adb3f0c2377c99677394d93134c878ab91af0

Checks will be approved automatically on success.