feat(jans-cedarling): include other algorithms in the benchmark tests

**Is your feature request related to a problem? Please describe.**

We currently only use HS256-signed tokens for the benchmarks and this might not be indicative of real-world performance.

**Describe the solution you'd like**

1. Add benchmarks for tokens signed with the following algorithms:
- RS256
- EC256
- EdDSA
2. Implement a function in the `test_utils` crate for generating signed tokens easily.

**Describe alternatives you've considered**

We could add more algorithms but running them might be too time-consuming.

**Additional context**

N/A