aws/logical: fix backend test (#13323)
aws/logical: fix backend test (#13323)

Remove the `[:64]` from
`TestAcceptanceBackend_AssumedRoleWithPolicyDoc()` since max length is
handled in `generateUniqueRoleName()`
rnaveiras/vault,hashicorp/vault,rnaveiras/vault,rnaveiras/vault,hashicorp/vault,rnaveiras/vault,hashicorp/vault,hashicorp/vault,rnaveiras/vault,hashicorp/vault,hashicorp/vault