feat: clean up deprecated items in api-mock of SDKs and protractor testing

[sdo-1A]

Proposed change

Cleanup of deprecated items in api-mock of showcase SDK and training SDK (and mustache file in @ama-sdk/schematics)

Related issues

- No issue associated -

[nx-cloud]

View your CI Pipeline Execution ↗ for commit da0c760.

Command	Status	Duration	Result
nx run-many --target=test-int	✅ Succeeded	1h 3m 26s	View ↗
nx run-many --target=build --projects=eslint-pl...	✅ Succeeded	<1s	View ↗
nx run-many --target=test-e2e	✅ Succeeded	9m 17s	View ↗
nx run-many --target=publish --nx-bail --userco...	✅ Succeeded	1m 46s	View ↗
nx affected --target=lint	✅ Succeeded	15m 26s	View ↗
nx run-many --target=build	✅ Succeeded	15m 5s	View ↗
nx affected --target=test --collectCoverage	✅ Succeeded	11m	View ↗
nx run ama-sdk-schematics:build-swagger	✅ Succeeded	<1s	View ↗
Additional runs (2)	✅ Succeeded	...	View ↗

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☁️ Nx Cloud last updated this comment at 2025-01-29 11:34:34 UTC

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 65.94%. Comparing base (3d57087) to head (da0c760).
Report is 2 commits behind head on release/12.0.0-next.

✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
...ages/@ama-sdk/core/src/clients/api-fetch-client.ts	0.00%	1 Missing ⚠️

Additional details and impacted files

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