Simplify F4Parser

[jackmoody11]

Patterns used in F4Parser can be improved by creating patterns via a function.

def f4_pattern(name: str):
    """Function to create regex pattern.

    Args:
        name (str): Name inside of angle brackets.

    Examples:
        
        >>> f4_pattern("nonDerivativeTransaction")
        '<nonDerivativeTransaction>(.*?)</nonDerivativeTransaction>'
    """
    return rf"<{name}>(.*?)</{name}>"