[CI] Add missing loader-robomeshcat dependency

Author: stephane-caron

tox.ini

@@ -65,6 +65,7 @@ commands =
 [testenv:loader-robomeshcat]
 deps =
     pytest
+    pycollada >=0.6
     robomeshcat >= 1.0.3
 commands =
     pytest --import-mode=importlib tests/loaders/test_robomeshcat.py