[DOC] Updated broken links in the README and contributing docs files

[nvamsikrishna05]

PR Description

Please describe the changes proposed in the pull request:

• Updated the Broken Links in the README and Contributing doc files.

**This PR resolves #817 **

PR Checklist

Please ensure that you have done the following:

1. PR in from a fork off your branch. Do not PR from <your_username>:dev, but rather from <your_username>:<feature-branch_name>.

2. If you're not on the contributors list, add yourself to AUTHORS.rst.

3. Add a line to CHANGELOG.md under the latest version header (i.e. the one that is "on deck") describing the contribution.
   • Do use some discretion here; if there are multiple PRs that are related, keep them in a single line.

Automatic checks

There will be automatic checks run on the PR. These include:

• Building a preview of the docs on Netlify
• Automatically linting the code
• Making sure the code is documented
• Making sure that all tests are passed
• Making sure that code coverage doesn't go down.

Relevant Reviewers

Please tag maintainers to review.

• @ericmjl
• @loganthomas
• @samukweku

[samukweku]

@nvamsikrishna05 have a look at the notebook and kindly resolve it, using the same idea as your other PR

[nvamsikrishna05]

@samukweku It's the same issue as other PR, so I am waiting for that PR to merge and will update this after that.

[ericmjl]

@nvamsikrishna05 we're good to merge in the latest dev branch! Can you do that? I'll be able to do a reviw shortly. 😄

[nvamsikrishna05]

@ericmjl Updated the PR. you can review it now. Thanks.

[loganthomas]

Looks good to me. Thanks @nvamsikrishna05!

[ericmjl]

With @samukweku and @loganthomas both finishing the review, I'm good to go too.

[ericmjl]

Thanks @nvamsikrishna05!