Use unique test names in TestvLLM

[dbarbuzzi]

SUMMARY:
This PR updates the TestvLLM class to pass the config file being tested as a parameter to the test. Functionally, this is no different than the existing behavior with regards to the test, but practically, it means that the config file will be included in the generated test name making it much easier to identify which config file is being tested across the board (in console output, in Testmo/reporting tools, etc.).

As a result, there is no longer a need for the previously added fixture that embedded the config file into the test suite metadata for downstream processing.

TEST PLAN:
A custom test run executing the e2e tests against this branch is here: https://github.com/neuralmagic/llm-compressor-testing/actions/runs/13138573134/job/36659921426
Reviewing the output of the 'run e2e tests' steps, the test names are updated:

• Old: TestvLLM.test_vllm
• New: TestvLLM_0_tests_e2e_vLLM_configs_fp8_dynamic_per_token_yaml.test_vllm

Note: The failures (RuntimeError: Failed to infer device type) are expected due to a recent change (seemingly on the vLLM side).

[github-actions]

👋 Hi! Thank you for contributing to llm-compressor. Please add the ready label when the PR is ready for review.

Note: This is required to complete the testing suite, please only add the label once the PR is code complete and local testing has been performed.

[brian-dellabetta]

I didn't know you could do this, awesome!