Hello,

I have recently noticed that a lot of connections with certain special characters don't work with SqlAlchemy as it requires the passwords to be [urlencoded when they contain special characters](https://stackoverflow.com/questions/1423804/writing-a-connection-string-when-password-contains-special-characters). 

Would there be any impact to changing the code at line 81 to urlencode the password like `urllib.parse.quote_plus(conn.password)` to prevent login failures for special characters? 

https://github.com/apache/airflow/blob/dee304b222d355b03794aa063f39e3ee13997730/airflow/hooks/dbapi_hook.py#L72-L88

I initially caught this issue while using the OdbcHook method found here. https://github.com/apache/airflow/blob/dee304b222d355b03794aa063f39e3ee13997730/airflow/providers/odbc/hooks/odbc.py#L198-L204

Happy to create a feature request, I just want to confirm that this issue makes sense. 


airflow/hooks/dbapi_hook.py
"""
        Dumps a database table into a tab-delimited file
        :param table: The name of the source table
        :type table: str
        :param tmp_file: The path of the target file
        :type tmp_file: str
        """
        raise NotImplementedError()
    def bulk_load(self, table, tmp_file):
        """
        Loads a tab-delimited file into a database table
        :param table: The name of the target table
        :type table: str
        :param tmp_file: The path of the file to load into the table
        :type tmp_file: str
        """
        raise NotImplementedError()