Masking pre-filled variables in .gitlab-ci.yml
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I am currently implementing a gitlab ci configuration using the pre-filled variables introduced in [issue 30101](https://gitlab.com/gitlab-org/gitlab/-/issues/30101/).
Some of these variables I would like to declare masked to prevent leaks of secrets as I intend to use these for access token and similar things, that should not be directly visible in the pipeline logs and probably also not necessarily in the input mask.
Example:
```
---
variables:
AZURE_TOKEN:
value: "this-is-not-a-valid-token"
description: "Please provide an access token to the azure cloud you want to get this file uploaded to."
masked: true
```
The `masked: true` part seems to not be implemented yet, or at least I wasn't able to find that in the issue description. I didn't do too much of a deep dive into the actual code changes.
issue