Adding pre-commit and some formatting

[lnxpy]

This PR contains:

• Ignoring test/third_party_tests/*.db (it gets generated whenever someone runs the tests)
• Adding pre-commit configurations (using black and check-docstring-first for better code quality insurance)

We can specify which docstring convention should be checked while committing.

⚠️ Based on the changes that I've made, source/dev-guide/contribute.html doc needs to be updated. I can work on them as well.

This PR closes #1347

[github-actions]

👋 Hello @lnxpy, thanks for submitting a EVA DB PR 🙏 To allow your work to be integrated as seamlessly as possible, we advise you to:

• ✅ Verify that your PR is up-to-date with georgia-tech-db/eva master branch. If your PR is behind you can update your code by clicking the 'Update branch' button or by running git pull and git merge master locally.
• ✅ Verify that all EVA DB Continuous Integration (CI) checks are passing.
• ✅ Reduce changes to the absolute minimum required for your bug fix or feature addition.

[lnxpy]

👋 Hello @lnxpy, thanks for submitting a EVA DB PR 🙏 To allow your work to be integrated as seamlessly as possible, we advise you to:

• ✅ Verify that your PR is up-to-date with georgia-tech-db/eva master branch. If your PR is behind you can update your code by clicking the 'Update branch' button or by running git pull and git merge master locally.
• ✅ Verify that all EVA DB Continuous Integration (CI) checks are passing.
• ✅ Reduce changes to the absolute minimum required for your bug fix or feature addition.

I think this CI message needs an update too. The default branch is staging not master.

[gaurav274]

@lnxpy Thanks for the effort, let me fix the build and then merge your PR.

[lnxpy]

Hi @gaurav274!
That's fine! Take your time. Before you merge this, please note that some changes should be made in the docs too.

I'm working on #1348 as well so the contribution guideline will need a major update after that.