revert remaining readonly on collection (#21051)

Author: solankisamir

specification/apimanagement/resource-manager/Microsoft.ApiManagement/preview/2022-04-01-preview/definitions.json

@@ -4202,7 +4202,6 @@
         "count": {
           "type": "integer",
           "format": "int64",
-          "readOnly": true,
           "description": "Total record count number."
         },
         "nextLink": {
@@ -4315,7 +4314,6 @@
         "count": {
           "type": "integer",
           "format": "int64",
-          "readOnly": true,
           "description": "Total record count number."
         }
       },
@@ -4334,7 +4332,6 @@
         "count": {
           "type": "integer",
           "format": "int64",
-          "readOnly": true,
           "description": "Total record count number."
         },
         "nextLink": {
@@ -4418,7 +4415,6 @@
         "count": {
           "type": "integer",
           "format": "int64",
-          "readOnly": true,
           "description": "Total record count number."
         },
         "nextLink": {
@@ -4655,7 +4651,6 @@
         "count": {
           "type": "integer",
           "format": "int64",
-          "readOnly": true,
           "description": "Total record count number."
         }
       },
@@ -5714,7 +5709,6 @@
         "count": {
           "type": "integer",
           "format": "int64",
-          "readOnly": true,
           "description": "Total record count number."
         },
         "nextLink": {
@@ -5788,7 +5782,6 @@
         "count": {
           "type": "integer",
           "format": "int64",
-          "readOnly": true,
           "description": "Total record count number."
         },
         "nextLink": {