[Engineering] Signing-up for GitLab: Add password strength validation when user signs up
## Problem
We are putting upfront our expectation for password, which is a good start. But we are not giving realtime feedback to the user on password creation which creates 2 problems:
* Interrupt the task as I need to quickly pause and assess if I comply with the password rules. This can add up to the cognitive load of the form.
* If I mistakingly forget one character, I will generate an error upon form submission.
## Input Data
* [NN/g disclosing password constraints](https://www.nngroup.com/videos/disclosing-password-constraints/)
* [NN/g Help People Create Passwords That They Can Actually Remember](https://www.nngroup.com/articles/passwords-memory/?lm=disclosing-password-constraints&pt=youtubevideo)
## Potential solution
Add visual cues to indicate that the password strength complies with our rules. Below a couple of potential MVC:
| Helper color update | Adding an Icon | Icon + Updating helper copy |
| ------ | ------ | ------ |
|  |  |  |
### MVC

#### [📐 Design Specs](https://www.figma.com/file/jHT2ebO6iA6P9wR8HX49AT/Sign-up-Improve-Password-field?node-id=1%3A3)
issue