Sonar dependency update, round 3.

Review Request #12469 — Created July 13, 2022 and submitted — Latest diff uploaded


This change updates a few more dependencies, and gets rid of some things
that we actually don't need:

  • Passport has been updated to the latest, and the slack stragegy has
    been switched over to a different implementation which is actually
    being maintained.
  • Changed to importing the standalone build for selectize, which lets us
    get rid of the explicit sifter dependency. sifter was depending on
    some vulnerable versions of other libraries. The standalone Selectize
    bundles a newer version of selectize which doesn't have this problem.
  • The published versions of scss libraries have some security problems.
    We're not importing any SCSS files, so all of this can just go away.
  • We're no longer using gulp-shell at all.

Verified that login/logout still worked correctly. Checked build and
basic functionality.