connector_importer: take full control of what are the required_keys

Not forcing required default value if required_keys_ignore_mapper and required_keys are defined in options.mapper.
Adding the new property required_keys_ignore_mapper in order to override the result of required_keys function

connector_importer/components/mapper.py

@@ -54,8 +54,16 @@ def required_keys(self, create=False):
         """
         req = dict(self.required)
         req.update(self.work.options.mapper.get("required_keys", {}))
+
+        if self.required_keys_ignore_mapper:
+            req = self.work.options.mapper.get("required_keys", {})
+
         return req
 
+    @property
+    def required_keys_ignore_mapper(self):
+        return self.work.options.mapper.get("required_keys_ignore_mapper", False)
+
     translatable = []
 
     def translatable_keys(self, create=False):