[TST] Fix for Issue #1184

[samukweku]

PR Description

Please describe the changes proposed in the pull request:

• Fix test fail for test_fill_missing_timestamps by provide first_time_stamp and last_time_stamp

This PR resolves #1184 .

PR Checklist

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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

[ericmjl]

🚀 Deployed on https://deploy-preview-1186--pyjanitor.netlify.app

[codecov]

Codecov Report

Merging #1186 (30b821b) into dev (32bd2ab) will decrease coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##              dev    #1186      +/-   ##
==========================================
- Coverage   97.69%   97.66%   -0.03%     
==========================================
  Files          76       76              
  Lines        3474     3474              
==========================================
- Hits         3394     3393       -1     
- Misses         80       81       +1     

[Zeroto521]

I'll merge this PR into #1143. See what happens.
So let this PR just keep opening.

[Zeroto521]

here we go