**Description**

It would be nice if the weight_rule default value could be managed by a global config

suggested config:
```
# Weighting method used for the effective total priority weight of the task. 
# Options are: { downstream | upstream | absolute } default is
default_weight_rule = downstream
```
**Use case / motivation**

In some pipeline, you really need to have absolute weight, and then you have to add a line in each task definition which is annoying

airflow/models/baseoperator.py
"""Metaclass of BaseOperator."""
    @classmethod
    def _apply_defaults(cls, func: T) -> T:
        """
        Function decorator that Looks for an argument named "default_args", and
        fills the unspecified arguments from it.
        Since python2.* isn't clear about which arguments are missing when
        calling a function, and that this can be quite confusing with multi-level
        inheritance and argument defaults, this decorator also alerts with
        specific information about the missing arguments.
        """
        
        
        
        
        sig_cache = signature(func)
        non_optional_args = {
            name
            for (name, param) in sig_cache.parameters.items()
            if param.default == param.empty
            and param.name != 'self'
            and param.kind not in (param.VAR_POSITIONAL, param.VAR_KEYWORD)
        }
        class autostacklevel_warn: