Fix CI badge in README and docs

[Anurag-Nagpal]

Description

Kindly take a look at CONTRIBUTING.md.

Please describe the purpose of this pull request. Reference and link to any relevant issues or pull requests.

Checklist

• [ ] Have you followed the guidelines in our Contributing document?
• [x] Have you checked to ensure there aren't any other open Pull Requests for the required change?
• [ ] Does your submission pass pre-commit? ($ pre-commit run --all-files or $ nox -s lint)
• [ ] Does your submission pass tests? ($ pytest or $ nox -s tests)
• [x] Does the documentation build with your changes? ($ cd docs; make clean; make html or $ nox -s docs)
• [ ] Does your submission pass the doctests? ($ xdoctest ./src/vector or $ nox -s doctests)

Before Merging

• [ ] Summarize the commit messages into a brief review of the Pull request.