Add Custom Activity User Elevation and scope and Databricks policyId (#12628)

* Add changes in pipeline.json for Custom Activity auto user specification and
Databricks linked services for policy id

* Update Pipeline.json

revert separate changes

* Update Pipeline.json

nit for camelcase field

* Update Pipeline.json

nit

Author: kesharma

specification/datafactory/resource-manager/Microsoft.DataFactory/stable/2018-06-01/entityTypes/LinkedService.json

@@ -5383,6 +5383,10 @@
         "encryptedCredential": {
           "type": "object",
           "description": "The encrypted credential used for authentication. Credentials are encrypted using the integration runtime credential manager. Type: string (or Expression with resultType string)."
+        },
+        "policyId": {
+          "type": "object",
+          "description": "The policy id for limiting the ability to configure clusters based on a user defined set of rules. Type: string (or Expression with resultType string)."
         }
       },
       "required": [

specification/datafactory/resource-manager/Microsoft.DataFactory/stable/2018-06-01/entityTypes/Pipeline.json

@@ -5562,6 +5562,10 @@
         "retentionTimeInDays": {
           "type": "object",
           "description": "The retention time for the files submitted for custom activity. Type: double (or Expression with resultType double)."
+        },
+        "autoUserSpecification": {
+          "type": "object",
+          "description": "Elevation level and scope for the user, default is nonadmin task. Type: string (or Expression with resultType double)."
         }
       },
       "required": [