[frontend] Implement JWT authentication for scripts in cta-admin-grpc
Description
This commit enables the JWT authentication mechanism for cta-admin-grpc, alongside Kerberos.
To specify which authentication method should be used, an environment variable CTA_ADMIN_GRPC_AUTH_METHOD is introduced.
The possible values are "jwt" and "krb5". If the variable is not set, then Kerberos authentication is attempted by default.
Checklist
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Documentation reflects the changes made. -
Merge Request title is clear, concise, and suitable as a changelog entry. See our contributing docs
References
Closes #1311 (closed), #1321 (closed), #1348 (closed)
Edited by Konstantina Skovola