Update AppRole API docs (#6047)
Update AppRole API docs (#6047)

- Use consistent "Create/Update" heading text style
kingland/vault,rnaveiras/vault,joelthompson/vault,hartsock/vault,hashicorp/vault,rnaveiras/vault,quixoten/vault,rnaveiras/vault,hartsock/vault,joelthompson/vault,joelthompson/vault,rnaveiras/vault,quixoten/vault,kingland/vault,hashicorp/vault,hartsock/vault,hashicorp/vault,hashicorp/vault,rnaveiras/vault,quixoten/vault,quixoten/vault,kingland/vault,kingland/vault,hashicorp/vault,hartsock/vault,kingland/vault,joelthompson/vault,hartsock/vault,hashicorp/vault