[ReleasePR operationalinsights] [OperationalInsights] Rename 'eTag' property to 'etag' (#2298)

Create to sync Azure/azure-rest-api-specs#18447
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Author: msftbot[bot]

schemas/2021-06-01/Microsoft.OperationalInsights.json

@@ -104,9 +104,9 @@
             "2021-06-01"
           ]
         },
-        "eTag": {
+        "etag": {
           "type": "string",
-          "description": "The ETag of the workspace."
+          "description": "The etag of the workspace."
         },
         "location": {
           "type": "string",