New preview site (#2036)

* Changes to DE preview site to support managed identity. Changes to
infrastructure to use new preview site.

* Fix formatting.

* Potential fix for code scanning alert no. 56: Server-side request forgery

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

* Use different secrets for subscription/tenant/client id's.

* Revert new id names.

* Update Az CLI config.

* Update to Node 18 and update security vulnerable dependencies.

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Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

preview/.azure/config

@@ -1,7 +1,7 @@
 [defaults]
-group = stfaul
-sku = P1v2
-appserviceplan = stfaul_asp_Linux_centralus_0
-location = centralus
-web = cosmos-explorer-preview
+group = dataexplorer-preview
+sku = P1V2
+appserviceplan = dataexplorer-preview
+location = westus2
+web = dataexplorer-preview