Change logger identifier from 'utils' to 'sdk-test-utils' for clarity (#3315)

## Summary

Addresses feedback on PR #3309 to use a more specific logger identifier
in test utilities, avoiding ambiguity with the source file's logger.

## Changes

- Changed logger identifier from `'utils'` to `'sdk-test-utils'` in
`packages/sdk/test/test-utils/utils.ts`

This prevents confusion in logs between the test utilities logger and
the identically-named logger in `packages/sdk/src/utils/utils.ts`.

## Checklist before requesting a review

- [ ] Is this a breaking change? If it is, be clear in summary.
- [x] Read through code myself one more time.
- [x] Make sure any and all `TODO` comments left behind are meant to be
left in.
- [x] Has reasonable passing test coverage?
- [ ] Updated changelog if applicable.
- [ ] Updated documentation if applicable.

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Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: mondoreale <[email protected]>

Author: Copilot

packages/sdk/test/test-utils/utils.ts

@@ -58,7 +58,7 @@ import { FakeStorageNode } from './../test-utils/fake/FakeStorageNode'
 import { addAfterFn } from './jest-utils'
 import { StreamIDBuilder } from '../../src/StreamIDBuilder'
 
-const logger = new Logger('utils')
+const logger = new Logger('sdk-test-utils')
 
 export function mockLoggerFactory(clientId?: string): LoggerFactory {
     return new LoggerFactory({