[Media] Removing required variables from MediaGraphSignalGateProcessor (#12323)

* minor changes to swagger

* reverting sdk definitions file

* removed value from required in parameterdefition

* removing required property from mediagraphsignalgateprocessor

* adding value back

Author: hivyas

specification/mediaservices/data-plane/LiveVideoAnalytics.Edge/preview/2.0.0/LiveVideoAnalytics.json

@@ -1090,11 +1090,6 @@
     },
     "MediaGraphSignalGateProcessor": {
       "type": "object",
-      "required": [
-        "activationSignalOffset",
-        "minimumActivationTime",
-        "maximumActivationTime"
-      ],
       "properties": {
         "activationEvaluationWindow": {
           "type": "string",