[ReleasePR imagebuilder] [Hub Generated] Review request for Microsoft.VirtualMachineImages to add version stable/2020-02-14 (#2045)

Create to sync Azure/azure-rest-api-specs#16725
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Author: msftbot[bot]

schemas/2020-02-14/Microsoft.VirtualMachineImages.json

@@ -661,7 +661,7 @@
         "vmSize": {
           "type": "string",
           "default": "",
-          "description": "Size of the virtual machine used to build, customize and capture images. Omit or specify empty string to use the default (Standard_D1_v2)."
+          "description": "Size of the virtual machine used to build, customize and capture images. Omit or specify empty string to use the default (Standard_D1_v2 for Gen1 images and Standard_D2ds_v4 for Gen2 images)."
         },
         "vnetConfig": {
           "oneOf": [