password verification after clicking on the Show secret variables button
Ask for another level of verification to check the user's identity. Much like what google and other services do.
This issue came forth from https://gitlab.com/gitlab-org/gitlab-ce/issues/21358#note_19121066
### proposal
this feature would be a mix between:
[hide-vars](/uploads/77225ab0eb7febb96ac0bf4c24b8bc78/hide-vars.gif)
and
[Secret_Variable_hidden](/uploads/5eb0b541e130f6207070b6b2c698a2ed/Secret_Variable_hidden.png)
[Secret_Variable_unlock](/uploads/e9d8573cc86ab1292c25ff73b83375db/Secret_Variable_unlock.png)
cc: @markpundsack @ayufan
issue