Add shutdown command to H3C interface template and update related configuration files

- Included the `shutdown` command in the H3C interface template to reflect the new interface state management.
- Updated the `config.conf` file to include the `shutdown` command for the `HundredGigE1/0/3` interface.
- Modified the expected output JSON to set the `shutdown` attribute to true, ensuring accurate testing and validation of interface configurations.

tests/fixtures/h3c/config.expected.json

@@ -63,7 +63,7 @@
     },
     {
       "interface": "HundredGigE1/0/3",
-      "shutdown": false,
+      "shutdown": true,
       "ip_address": null,
       "mask": null,
       "description": "HW_TEST_1"