Fix stg_customers spelling (#4656)

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Changing a misspelling of `stg_cusutomers` to `stg_customers`.


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Thank you very much for the clear effort put in to this documentation by
the way. It was very helpful in getting a demo project set up.

website/docs/guides/snowflake-qs.md

@@ -462,7 +462,7 @@ Sources make it possible to name and describe the data loaded into your warehous
 
 5. Execute `dbt run`. 
 
-    The results of your `dbt run` will be exactly the same as the previous step. Your `stg_cusutomers` and `stg_orders`
+    The results of your `dbt run` will be exactly the same as the previous step. Your `stg_customers` and `stg_orders`
     models will still query from the same raw data source in Snowflake. By using `source`, you can
     test and document your raw data and also understand the lineage of your sources.