tools (common/template): skip empty icon names in _icon_defs

libervia/backend/tools/common/template.py

@@ -1056,6 +1056,8 @@ class Renderer:
         )
         defs_elt = etree.SubElement(svg_elt, "defs")
         for name in names:
+            if not name:
+                continue
             if "/" in name:
                 raise ValueError("SVG name must not have a `/` in it.")
             for style_name in ("regular", "brands", "solid"):