Updates version to 2024.1.2

[ilumsden]

This PR updates the version to 2024.1.2. The release notes for this version are below (in GitHub Markdown format this time, so no need for stupid Slack->GitHub conversion).

Version 2024.1.2 is a minor release on the 2024.1 series.

Notable Changes:

• Adds support for multi-indexed column names to the query language (Adds support for multi-indexed column names #124)
• Adds a new HPCToolkit reader supporting the newest database format (feature: importing HPCToolkit data into Hatchet #126)
• Fixes a bug in Roundtrip that causes interactive visualization to fail in newer versions of Jupyter and IPython (Fix Bug When Importing Roundtrip #127)

Internal Updates:

• Adds functionality to CI that auto-uploads to Codecov (Fixes common formatting issues messing with CI #130)
• Upgrades the version of black used in CI (Upgrades the version of black used in CI #131)
• Upgrades action versions in CI/CD (Hotfix: upgrades versions for GitHub Actions #132)