Support specifying additional AWS IAM trust relationships for roles managed by Otterize

[orishoshan]

Description

Specify the following annotation on a pod to add an additional trust relationship statement:

credentials-operator.otterize.com/additional-role-trust-relationship-statements: '[{"Effect": "Allow", "Principal": {"AWS": "*"}, "Action": ["sts:AssumeRoleWithWebIdentity"]}]'

References

Functionality change that goes together with a matching PR in the intents-operator repo: otterize/intents-operator#589

Testing

• This change adds test coverage for new/changed/fixed functionality

Checklist

• I have added documentation for new/changed functionality in this PR and in github.com/otterize/docs