chore(ci): change image from ubuntu-24.04 to ubuntu-latest

[danceratopz]

🗒️ Description

#792 changed the images used from ubuntu-latest to ubuntu-24.04 (latest pointed to ubuntu-22.04 at the time). This PR reverts this change as latest has been bumped to ubuntu-24.04 in Github Actions in actions/runner-images@ae99c16.

Using ubuntu-latest simplified the need to use -P to map the image correctly. The following is from the never published and now defunct docs:

"Specifying the `ubuntu-24.04` docker image"

    [#792](https://github.com/ethereum/execution-spec-tests/pull/792/) made EELS the default `t8n` tool. Our Github workflows were changed to use the `ubuntu-24.04` docker image which has OpenSSL 3.0.7, required by EELs to have RIPEMD160 support (used by the precompile at `0x03`). As of 2024-09-30 `ubuntu-latest` resolves to `ubuntu-22-04`.

    To run workflows that use `ubuntu-24.04` with `act` (as of version 0.2.67) the following must be added to the command-line:

    ```bash
    -P ubuntu-24.04=ghcr.io/catthehacker/ubuntu:full-24.04
    ```

🔗 Related Issues

#792

✅ Checklist

• All: Set appropriate labels for the changes.
• All: Considered squashing commits to improve commit history.
• All: Added an entry to CHANGELOG.md. skipped
• All: Considered updating the online docs in the ./docs/ directory.
• Tests: All converted JSON/YML tests from ethereum/tests have been added to converted-ethereum-tests.txt.
• Tests: A PR with removal of converted JSON/YML tests from ethereum/tests have been opened.
• Tests: Included the type and version of evm t8n tool used to locally execute test cases: e.g., ref with commit hash or geth 1.13.1-stable-3f40e65.
• Tests: Ran mkdocs serve locally and verified the auto-generated docs for new tests in the Test Case Reference are correctly formatted.

[marioevz]

LGTM!