Change --env-exclude-sensitive-key to --env-allow-sensitive-key

[matglas]

The current implementation is --env-exclude-sensitive-key and it excludes it from the sensitive-key list. But it is a confusing name. --env-allow-sensitive-key is a much better name and captures the essence namekly, you have a key in the variables that normally is considered sensitive but you want to allow it to be captured.

Thank @jkjell for pointing this out.

• chore: Add documentation on environment attestor #555 (comment)