set dash-bootstrap-components version (#392)

dash-bootstrap-components v1 requires dash 2

Author: rosscg

requirements.txt

@@ -5,7 +5,7 @@ dash-renderer
 plotly
 dpd-components
 
-dash-bootstrap-components
+dash-bootstrap-components<1
 
 channels<3.0
 Django>=2.2,<4.0.0