minor fixes to WRF.md

WRF.md

@@ -7,7 +7,7 @@ Besides this basic guide, more detailed information is available too:
 [Basic WRF usage, including compilation instructions](WRF/WRF_basic.md).  
 [Advanced WRF usage](WRF/WRF_basic.md).  
 [Data assimilation with WRF](WRF/WRF_da.md).  
-[Workflows for common WRF tasks](WRF/WRF_da.md).
+[Workflows for common WRF tasks](WRF/WRF_da.md).  
 [Configuration files on different servers](WRF/config_files).  
 
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