g.10.28.graphml in rgl-0.5.10

- old
+ new

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!-- This file was written by the internal XML-Handler of Y-Files.-->
-<!DOCTYPE graphml SYSTEM "http://www.graphdrawing.org/dtds/graphml.dtd">
+<!DOCTYPE graphml SYSTEM "https://www.graphdrawing.org/dtds/graphml.dtd">
 <graphml>
 <graph id="G">
 <node id="n0"/>
 <node id="n1"/>
 <node id="n2"/>
\ No newline at end of file