azure-cli: Set AzureCLIPath environment variable (#1469)

As identified in, e.g., [the Azure Go SDK][1] and [other Azure SDKs][2],
the Azure CLI program can be resolved using an environment variable
called AzureCLIPath or AZURE_CLI_PATH if the program is not installed to
the default locations. Setting this environment variable allows programs
such as Pulumi which (ultimately) build on the Azure SDKs to resolve the
CLI program when it has been installed with Scoop.

  [1]: afe17657e2/autorest/azure/cli/token.go (L151)
  [2]: https://github.com/search?q=org%3AAzure+AzureCLIPath&type=code

bucket/azure-cli.json

@@ -13,5 +13,9 @@
     },
     "autoupdate": {
         "url": "https://azurecliprod.azureedge.net/msi/azure-cli-$version.msi"
+    },
+    "env_set": {
+        "AzureCLIPath": "$dir",
+        "AZURE_CLI_PATH": "$dir"
     }
 }