fix(core): fixed cache.clear() not working as expected

[yuhengshs]

Description of changes

The purpose of this PR is to fix the issue that Cache.clear() is not working as expected by not clearing the cache.

• Added prefix to the key to make sure the item is successfully identified and removed.
• Updated the unit test to prevent missing prefix and not clearing cache

Issue #, if available

13791

Description of how you validated changes

Checklist

• PR description included
• yarn test passes
• Unit Tests are changed or added
• Relevant documentation is changed or added (and PR referenced)

Checklist for repo maintainers

• Verify E2E tests for existing workflows are working as expected or add E2E tests for newly added workflows
• New source file paths included in this PR have been added to CODEOWNERS, if appropriate

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.