Update netlify.toml

Author: Ajay-singh1

netlify.toml

@@ -1,6 +1,14 @@
 [build]
-    publish = "public"
-
+  publish = "public"
+  command = """
+    if [ \"$CONTEXT\" = \"production\" ]; then
+      hugo --baseURL=\"https://istio.io/\"
+    elif [ \"$CONTEXT\" = \"deploy-preview\" ]; then
+      hugo --baseURL=\"$DEPLOY_PRIME_URL/\"
+    else
+      hugo --baseURL=\"https://preliminary.istio.io/\"
+    fi
+  """
 [build.environment]
     # Consult the Docs WG before bumping Hugo.
     # Specifically, the version here should match docker/build-tools/Dockerfile in istio/tools,
@@ -21,4 +29,4 @@
 
 [[edge_functions]]
   path = "/v*"
-  function = "redirect-to-latest"
+  function = "redirect-to-latest"