OPDS: Also handle self-closing dc: tags (#7900)

Fix #7899

plugins/opds.koplugin/opdsparser.lua

@@ -75,7 +75,7 @@ function OPDSParser:parse(text)
     -- luxl doesn't handle XML comments, so strip them
     text = text:gsub("<!%-%-.-%-%->", "")
     -- luxl is also particular about the syntax for self-closing, empty & orphaned tags...
-    text = text:gsub("<(%l+)/>", "<%1 />")
+    text = text:gsub("<([%l:]+)/>", "<%1 />")
     -- We also need to handle the slash-less variants for br & hr...
     text = text:gsub("<([bh]r)>", "<%1 />")
     -- Some OPDS catalogs wrap text in a CDATA section, remove it as it causes parsing problems