[YANG] Add missing entry for sonic-srv6.yang in sonic-yang-models/set…

…up.py

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#### Why I did it

Previously, I did not add an entry in setup.py to install the srv6 yang model

##### Work item tracking
- Microsoft ADO **(number only)**:

#### How I did it

Add the missing entry for sonic-srv6.yang in sonic-yang-models/setup.py

#### How to verify it

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src/sonic-yang-models/tests/files/sample_config_db.json

@@ -2806,6 +2806,17 @@
                 "prefix": "fcbb:bbbb:1::"
             }
         },
+        "SRV6_MY_SIDS": {
+            "loc1|fcbb:bbbb:1::/48": {
+                "action": "uN",
+                "decap_dscp_mode": "pipe"
+            }
+        },
+        "SRV6_MY_LOCATORS": {
+            "loc1": {
+                "prefix": "fcbb:bbbb:1::"
+            }
+        },
         "SRV6_MY_SIDS": {
             "loc1|fcbb:bbbb:1::/48": {
                 "action": "uN",