fix(ci): add solc-select to fill stage of build fixtures

[spencer-tb]

🗒️ Description

Fixes the new solc-select dependency required to build fixtures, for both stable/develop fixture releases as well and feature (EOF/Verkle) fixture releases.

🔗 Related Issues

This was an oversight from the following PR: #604

✅ Checklist

• All: Set appropriate labels for the changes.
• All: Considered squashing commits to improve commit history.
• All: Added an entry to CHANGELOG.md - no addition.
• 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: 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.

[danceratopz]

Thanks for jumping in here!

[danceratopz]

LGTM!