MAINT: use jupyter builder to filter header for download notebook (#360)

Author: mmcky

lectures/geom_series.md

@@ -12,7 +12,7 @@ kernelspec:
 ---
 
 (geom_series)=
-```{raw} html
+```{raw} jupyter
 <div id="qe-notebook-header" style="text-align:right;">
         <a href="https://quantecon.org/" title="quantecon.org">
                 <img style="width:250px;display:inline;" src="https://assets.quantecon.org/img/qe-menubar-logo.svg" alt="QuantEcon">