v2.4.2: don't need OPA_SECRET as admin_secret

Following up on CanDIG/candig-opa#62: we don't need the OPA_SECRET anymore.

What's Changed

• Use getpass for user password so password is not displayed or logged by @mshadbolt in #24
• Bump requests from 2.26.0 to 2.32.2 by @dependabot in #25
• DIG-1652: don't pass on admin_secret to opa calls by @daisieh in #26

New Contributors

• @dependabot made their first contribution in #25

Full Changelog: v2.4.1...v2.4.2