fixed broken namespace urls (http not https)

Author: gabrielbodard

guidelines/xml/ex-epidoctemplate.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<?xml-model href="https://epidoc.stoa.org/schema/latest/tei-epidoc.rng" schematypens="https://relaxng.org/ns/structure/1.0"?>
-<?xml-model href="https://epidoc.stoa.org/schema/latest/tei-epidoc.rng" schematypens="https://purl.oclc.org/dsdl/schematron"?>
+<?xml-model href="https://epidoc.stoa.org/schema/latest/tei-epidoc.rng" schematypens="http://relaxng.org/ns/structure/1.0"?>
+<?xml-model href="https://epidoc.stoa.org/schema/latest/tei-epidoc.rng" schematypens="http://purl.oclc.org/dsdl/schematron"?>
 <TEI xmlns="http://www.tei-c.org/ns/1.0" xml:space="preserve" xml:lang="en">
     <teiHeader>
         <fileDesc>