feat(surveys): optional questions for multipleq

[liyiy]

Problem

Multiple questions should support optional questions

To go in with PostHog/posthog-js#826

Changes

👉 Stay up-to-date with PostHog coding conventions for a smoother review.

How did you test this code?

[neilkakkar]

With the way things stand, optional doesn't really make sense with the link type question, does it, since there's no way to skip it even if its optional

[liyiy]

With the way things stand, optional doesn't really make sense with the link type question, does it, since there's no way to skip it even if its optional

We can put in a "skip" or "next" button in the site app so users don't HAVE to click on the link but it doesn't seem that big of a deal 👀 since users have to click on a button to go next either way, and the link doesn't hurt from being opened. Alternatively, I can also remove the checkbox from link type questions if you think that makes a lot more sense.

[neilkakkar]

no strong opinions about it, however you feel works best is good, just wanted to make sure you've thought about it 👍