Make sure the '*' is after the path and not before for the Files:

036147cd · Filippo Rusconi · 910d6a24 · 036147cd
Commit 036147cd authored Nov 09, 2020 by Filippo Rusconi
--- a/debian/copyright
+++ b/debian/copyright
@@ -79,7 +79,7 @@ Files: src/resources/icons/mit/jamicons/*
 Copyright: 2017-2020 Michael Amprimo <https://github.com/michaelampr/jam>
 License: MIT

-Files: */src/resources/html_doc
+Files: src/resources/html_doc/*
 Copyright: The Global Proteome Machine Organization <https://www.thegpm.org/TANDEM/>
 License: Artistic