Align privacy statement prompt behavior

[aaronlew02]

Description

Before #4959, signers using Rekor via the TUF signing config were required to agree to a privacy statement, including an immutable record warning.

However, signers using Rekor via a manually-provided signing config were not required to agree to the statement.

Furthermore, #4959 requires that ALL signers with a signing config containing ANY transparency log(s) are required to agree to the statement.

For the sake of consistency, this issue proposes either:

• removing the privacy statement, or
• limiting the requirement to all signers using Rekor.

[tzprograms]

Can I take up this issue ?

[Hayden-IO]

The linked PR hasn’t landed yet and there are still discussions with the LF regarding how to proceed.