[devtools] Fix database creation issues for CubicWebTestTC tests To reproduce (with a purged repo): * python web/test/test_jscript.py * python web/test/unittest_views_xmlrss.py The '__default_empty_db__' will contain the wrong 'base_url' configuration, thus breaking URLs in the xmlrss tests. Closes #9297611.

cubicweb-web: embedded-javascript-library usr/share/cubicweb/cubes/shared/data/jquery.js