enable managed data plane annotation on ASM submodule

[szihai]

TL;DR

For later versions of Managed ASM, MDP is enabled by default. But the module should also have a switch to disable it.

Terraform Resources

No response

Detailed design

https://cloud.google.com/service-mesh/docs/managed/provision-managed-anthos-service-mesh-asmcli#disable_the_managed_data_plane_optional
lists the step to disable MDP. For NS and application level operations, it is reasonable to do it adhoc using kubectl command.
But for cluster level operation, it is better to expose the variable and make it available.

Additional information

No response