add .env for vscode web

Author: Shreyas-Microsoft

infra/vscode_web/.env

@@ -0,0 +1,7 @@
+AZURE_EXISTING_AGENT_ID="<%= agentId %>"
+AZURE_ENV_NAME="<%= playgroundName %>"
+# AZURE_LOCATION="<%= location %>"
+AZURE_SUBSCRIPTION_ID="<%= subscriptionId %>"
+AZURE_EXISTING_AIPROJECT_ENDPOINT="<%= endpoint %>"
+AZURE_EXISTING_AIPROJECT_RESOURCE_ID="<%= projectResourceId %>"
+AZD_ALLOW_NON_EMPTY_FOLDER=true