chore: set protocol for npm to https

[ph-fritsche]

Why:

npm notice Beginning October 4, 2021, all connections to the npm registry - including for package installation - must use TLS 1.2 or higher. You are currently using plaintext http to connect.

Checklist:

• Ready to be merged

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit 91a670d:

Sandbox	Source
react-testing-library-examples	Configuration

[codecov]

Codecov Report

Merging #1051 (91a670d) into main (ca22d25) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##              main     #1051   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           25        25           
  Lines          919       919           
  Branches       283       283           
=========================================
  Hits           919       919           

Flag	Coverage Δ
node-12	100.00% <ø> (ø)
node-14	100.00% <ø> (ø)
node-16.9.1	100.00% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update ca22d25...91a670d. Read the comment docs.

[github-actions]

🎉 This PR is included in version 8.9.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀