fix tests

tracim/tests/functional/test_system.py

         application = res[1]
         assert application['label'] == "Markdown Plus Documents"
         assert application['slug'] == 'contents/markdownpluspage'
-        assert application['fa_icon'] == 'file-code'
+        assert application['fa_icon'] == 'file-code-o'
         assert application['hexcolor'] == '#f12d2d'
         assert application['is_active'] is True
         assert 'config' in application
         application = res[4]
         assert application['label'] == "Calendar"
         assert application['slug'] == 'calendar'
-        assert application['fa_icon'] == 'calendar-alt'
+        assert application['fa_icon'] == 'calendar'
         assert application['hexcolor'] == '#757575'
         assert application['is_active'] is True
         assert 'config' in application
 
         content_type = res[2]
         assert content_type['slug'] == 'markdownpage'
-        assert content_type['fa_icon'] == 'file-code'
+        assert content_type['fa_icon'] == 'file-code-o'
         assert content_type['hexcolor'] == '#f12d2d'
         assert content_type['label'] == 'Rich Markdown File'
         assert content_type['creation_label'] == 'Create a Markdown document'

tracim/tests/functional/test_user.py

         assert sidebar_entry['label'] == 'Dashboard'
         assert sidebar_entry['route'] == '/#/workspaces/1/dashboard'  # nopep8
         assert sidebar_entry['hexcolor'] == "#252525"
-        assert sidebar_entry['fa_icon'] == ""
+        assert sidebar_entry['fa_icon'] == "signal"
 
         sidebar_entry = workspace['sidebar_entries'][1]
         assert sidebar_entry['slug'] == 'contents/all'
         assert sidebar_entry['label'] == 'All Contents'
         assert sidebar_entry['route'] == "/#/workspaces/1/contents"  # nopep8
         assert sidebar_entry['hexcolor'] == "#fdfdfd"
-        assert sidebar_entry['fa_icon'] == ""
+        assert sidebar_entry['fa_icon'] == "th"
 
         sidebar_entry = workspace['sidebar_entries'][2]
         assert sidebar_entry['slug'] == 'contents/html-documents'
         assert sidebar_entry['label'] == 'Markdown Plus Documents'
         assert sidebar_entry['route'] == "/#/workspaces/1/contents?type=markdownpluspage"    # nopep8
         assert sidebar_entry['hexcolor'] == "#f12d2d"
-        assert sidebar_entry['fa_icon'] == "file-code"
+        assert sidebar_entry['fa_icon'] == "file-code-o"
 
         sidebar_entry = workspace['sidebar_entries'][4]
         assert sidebar_entry['slug'] == 'contents/files'
         assert sidebar_entry['label'] == 'Calendar'
         assert sidebar_entry['route'] == "/#/workspaces/1/calendar"  # nopep8
         assert sidebar_entry['hexcolor'] == "#757575"
-        assert sidebar_entry['fa_icon'] == "calendar-alt"
+        assert sidebar_entry['fa_icon'] == "calendar"
 
     def test_api__get_user_workspaces__err_403__unallowed_user(self):
         """

tracim/tests/functional/test_workspaces.py

         assert sidebar_entry['label'] == 'Dashboard'
         assert sidebar_entry['route'] == '/#/workspaces/1/dashboard'  # nopep8
         assert sidebar_entry['hexcolor'] == "#252525"
-        assert sidebar_entry['fa_icon'] == ""
+        assert sidebar_entry['fa_icon'] == "signal"
 
         sidebar_entry = workspace['sidebar_entries'][1]
         assert sidebar_entry['slug'] == 'contents/all'
         assert sidebar_entry['label'] == 'All Contents'
         assert sidebar_entry['route'] == "/#/workspaces/1/contents"  # nopep8
         assert sidebar_entry['hexcolor'] == "#fdfdfd"
-        assert sidebar_entry['fa_icon'] == ""
+        assert sidebar_entry['fa_icon'] == "th"
 
         sidebar_entry = workspace['sidebar_entries'][2]
         assert sidebar_entry['slug'] == 'contents/html-documents'
         assert sidebar_entry['label'] == 'Markdown Plus Documents'
         assert sidebar_entry['route'] == "/#/workspaces/1/contents?type=markdownpluspage"    # nopep8
         assert sidebar_entry['hexcolor'] == "#f12d2d"
-        assert sidebar_entry['fa_icon'] == "file-code"
+        assert sidebar_entry['fa_icon'] == "file-code-o"
 
         sidebar_entry = workspace['sidebar_entries'][4]
         assert sidebar_entry['slug'] == 'contents/files'
         assert sidebar_entry['label'] == 'Calendar'
         assert sidebar_entry['route'] == "/#/workspaces/1/calendar"  # nopep8
         assert sidebar_entry['hexcolor'] == "#757575"
-        assert sidebar_entry['fa_icon'] == "calendar-alt"
+        assert sidebar_entry['fa_icon'] == "calendar"
 
     def test_api__get_workspace__err_403__unallowed_user(self) -> None:
         """