Makes sure dictionary of capabilities includes required options, and does not include protected ones.
    :param capabilities:
    :return: dict

def sanitise_capabilities(capabilities):
    """
    Makes sure dictionary of capabilities includes required options, and does not include protected ones.
    :param capabilities:
    :return: dict
    """
    for c in REQUIRED_CAPABILITIES:
        capabilities[c] = options[c]

    for c in PROTECTED_CAPABILITIES:
        if c in capabilities:
            del capabilities['client_secret']

    return capabilities