tweaks

    >>> fr2.add_record(filepath="test2.txt", db=False, comment="test file 2")

    >>> fr_all = FileRecorder([*fr1, *fr2])

    >>> fr_all.pprint_all()

    <FileRecorder length=2>

     filepath   db    comment   existence

    --------- ----- ----------- ---------

    test1.txt False test file 1     False

    test2.txt False test file 2     False

    >>> fr_all.extend(fr1)

    >>> fr_all.pprint_all()

    <FileRecorder length=3>

     filepath   db    comment   existence

    --------- ----- ----------- ---------

    test1.txt False test file 1     False

    test2.txt False test file 2     False

    test1.txt False test file 1     False

``csst_common.logger.get_logger()``

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