fix: Error fix for v2 module due to missing tcp_socket attribute

[rara-tan]

What I did

I added the tcp_socket attribute to the variables.tf of the v2 modules.

Errors

When I use the v2 module, I encountered the following error.

╷
│ Error: Unsupported attribute
│
│   on main.tf line 149, in resource "google_cloud_run_v2_service" "main":
│  149:               for_each = liveness_probe.value.tcp_socket[*]
│     ├────────────────
│     │ liveness_probe.value is object with 6 attributes
│
│ This object does not have an attribute named "tcp_socket".

Why

There is a tcp_socket section on the main.tf ( https://github.com/GoogleCloudPlatform/terraform-google-cloud-run/blob/main/modules/v2/main.tf#L182-L187 ).
However, there is no tcp_socket section on the variables.tf ( https://github.com/GoogleCloudPlatform/terraform-google-cloud-run/blob/main/modules/v2/variables.tf#L283-L301 )