chore: replace jest with mocha VSCODE-516 (#668)

Author: mcasimir

.depcheckrc

@@ -15,3 +15,5 @@ ignores:
  - node-loader
  - ts-loader
  - mongodb-runner
+ - tabbable # Mocha register testing workaround stub.
+ - ejson-shell-parser # Used by the connection-form.