Delete mypy settings from pyproject.toml

[gerlero]

Removed mypy configuration from pyproject.toml

[Copilot]

Pull Request Overview

This PR removes the mypy type checking configuration from the project's pyproject.toml file, eliminating static type checking setup for the multicollections and tests packages.

• Removes the entire [tool.mypy] configuration section
• Eliminates mypy's strict mode and explicit-override error code settings
• Removes package specifications for multicollections and tests directories

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (fcd1695) to head (e0c5b39).

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #87   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            3         3           
  Lines          352       352           
=========================================
  Hits           352       352           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.