docs: Add examples using network_state variable

[liangwen12year]

Enhancement:

Reason:

Result:

Issue Tracker Tickets (Jira or BZ if any):

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Project coverage is 43.29%. Comparing base (89d7148) to head (398678d). Report is 7 commits behind head on main.

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[liangwen12year]

@tyll , configure vrf interface is not supported in network_connections, besides that, I also added other examples.

[liangwen12year]

    - name: Configure the vrf interface test-vrf0 with vrf port eth1 and vrf route table 101
      vars:
        network_state:
          interfaces:
            - name: test-vrf0
              type: vrf
              state: up
              vrf:
                port:
                  - eth1
                route-table-id: 101
      ansible.builtin.include_role:
        name: linux-system-roles.network

@eliaswimmer, this is the example of configuring vrf interface using the network_state variable.