Initially hide environment variable values in Settings page

[spoenemann]

Gitpod environment variables are often used to store secrets such as access tokens for npm etc. I think the Settings page should hide the variable values initially and offer buttons (:eye:) to show individual values.

Example situation where this is relevant: During a video call with screen sharing the presenter wants to add / change an env variable. Other participants of that call would see the whole mapping of env variables, which could be problematic in some circumstances.

[Kreyren]

Agree, i had to change the tokens twice by now, because it got leaked through similar scenario.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.