[yang]: Add yang model for dpu database service (#17191)

### Why I did it
According to the design, the database instances of DPU will be kept in the NPU host.

### How I did it
Declare a new field, `has_per_dpu_scope`, in the config_db for database feature.

#### How to verify it
Check Azp

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

@@ -1825,6 +1825,7 @@
                 "auto_restart": "always_enabled",
                 "has_global_scope": "true",
                 "has_per_asic_scope": "true",
+                "has_per_dpu_scope": "true",
                 "delayed": "false",
                 "high_mem_alert": "disabled",
                 "state": "always_enabled",

src/sonic-yang-models/tests/yang_model_tests/tests_config/feature.json

@@ -10,6 +10,7 @@
                         "delayed": "False",
                         "has_global_scope": "True",
                         "has_per_asic_scope": "True",
+                        "has_per_dpu_scope": "True",
                         "set_owner": "local",
                         "check_up_status": "False",
                         "support_syslog_rate_limit": "true"

src/sonic-yang-models/yang-models/sonic-feature.yang

@@ -78,6 +78,13 @@ module sonic-feature{
                     default "false";
                 }
 
+                leaf has_per_dpu_scope {
+                    description "This configuration identicates there will only one service
+                                spawned per DPU";
+                    type feature-scope-status;
+                    default "false";
+                }
+
                 leaf high_mem_alert {
                     description "This configuration controls the trigger to generate
                                 alert on high memory utilization";