Issue 1311 - change let to const

[sandeshShahapur]

Fixes #1311

• [x] PR is descriptively titled 📑 and links the original issue above 🔗
• [x] tests pass -- look for a green checkbox ✔️ a few minutes after opening your PR -- or run tests locally with grunt test
• [x] code is in uniquely-named feature branch and has no merge conflicts 📁
• [ ] screenshots/GIFs are attached 📎 in case of UI updates
• [x] @mention the original creator of the issue in a comment below for help or for a review

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[segun-codes]

Great effort @sandeshShahapur, many thanks!

@TildaDares, @cesswairimu you may now want to consider this PR for merging.

[cesswairimu]

Thanks a lot @segun-codes for the fto :100:

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[7malikk]

Congratulations on your merge @sandeshShahapur 🎊