[FIX] server: avoid crash on model not in a module

If a model is not declared in a valid odoo module, the code is actually crashing.
This commit prevent it and return the symbol even if the dependencies are not valid, as it can't be evaluated.
This is not a really nice case, but having a model declaration outside of a module is not really somthing that should happen

Author: fda-odoo

server/core/model.py

@@ -19,7 +19,7 @@ def get_main_symbols(self, from_module = None, module_acc:set = None):
         res = []
         for sym in self.impl_sym:
             if sym.modelData.name not in sym.modelData.inherit:
-                if not from_module or \
+                if not from_module or not sym.get_module_symbol() or \
                 (module_acc and sym.get_module_sym().dir_name in module_acc) or \
                 from_module.is_in_deps(sym.get_module_sym().dir_name, module_acc):
                     res.append(sym)