Add password attribute to input variable type "promptString"

[jlittorin]

It should be possible to enter a value for an input variable without having the UI show what is typed by setting a password attribute for the variable to true:

"inputs": [
  {
    "id": "authPassword",
    "type": "promptString",
    "description": "Password for authentication",
    "password": true
  }
]

[vscodebot]

(Experimental duplicate detection)
Thanks for submitting this issue. Please also check if it is already covered by an existing one, like:

• git push to a remote with an ssh password (#69033)