When using the ControlPanel's bottom-right slot in another component, if
`viewSwitcherEntries` wasn't defined in `env.config` it would raise a
traceback, as the template would try to check an `undefined`'s length.
Removed the workaround that added an empty `viewSwitcherEntries` in the
forecast report and the bom overview report since it's no longer
necessary.
closesodoo/odoo#112415
Signed-off-by: Aaron Bohy (aab) <aab@odoo.com>