Extended CREATE_FILE_REGEX to match html/htm files

[frappelatte28]

Fixes #1749
Modified CREATE_FILE_REGEX variable to match html/htm file extensions too.
I have verified that this pull request:

• [ x] has no linting errors (npm run lint)
• [ x] is from a uniquely-named feature branch and has been rebased on top of the latest develop branch. (If I was asked to make more changes, I have made sure to rebase onto develop then too)
• [ x] is descriptively named and links to an issue number, i.e. Fixes #123

[frappelatte28]

@catarak kindly review this PR :)

[frappelatte28]

here is the gif showing the same

[catarak]

Thank you! Working great for me 🎉