feat(jans-cedarling): implement benchmarks for startup and authz

[rmarinn]

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Description

This PR implements benchmarks for the following metrics:

• Startup time: How long Cedarling takes to initialize.
• Authorization time: The time taken to process an authorization request.

Target issue

closes #10773

Implementation Details

Benchmarks are in the /cedarling/src/benches directory.

Benchmarks can be ran using cargo bench -p cedarling.

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Test and Document the changes

• Static code analysis has been run locally and issues have been fixed
• Relevant unit and integration tests have been added/updated
• Relevant documentation has been updated if any (i.e. user guides, installation and configuration guides, technical design docs etc)

Please check the below before submitting your PR. The PR will not be merged if there are no commits that start with docs: to indicate documentation changes or if the below checklist is not selected.

• I confirm that there is no impact on the docs due to the code changes in this PR.