[Doc] Fix argument in example for databricks_custom_app_integration (#4132)

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Author: alexott

docs/resources/custom_app_integration.md

@@ -15,7 +15,7 @@ resource "databricks_custom_app_integration" "this" {
     redirect_urls = ["https://example.com"]
     scopes = ["all-apis"]
     token_access_policy {
-        access_token_ttl_in_minutes = %s
+        access_token_ttl_in_minutes = 15
         refresh_token_ttl_in_minutes = 30
     }
 }