Do not report wrong indentation in tables

[wouterj]

https://github.com/symfony/symfony-docs/pull/14521/checks?check_run_id=1359758355

The following table is marked as invalid by DOCtor:

=======================  ====================================================  ==========================
Option                   Description                                           Default
=======================  ====================================================  ==========================
``csv_delimiter``        Sets the field delimiter separating values (one       ``,``
                         character only)
``csv_enclosure``        Sets the field enclosure (one character only)         ``"``
``csv_escape_char``      Sets the escape character (at most one character)
``csv_key_separator``    Sets the separator for array's keys during its        ``.``
                         flattening
``csv_headers``          Sets the headers for the data                         ``[]``, inferred from input data's keys
``csv_escape_formulas``  Escapes fields containg formulas by prepending them   ``false``
                         with a ``\t`` character
``as_collection``        Always returns results as a collection, even if only
                         one line is decoded.
``no_headers``           Disables header in the encoded CSV                    ``false``
``output_utf8_bom``      Outputs special `UTF-8 BOM`_ along with encoded data  ``false``
=======================  ====================================================  ==========================

The indentation is 25 lines, which isn't dividable by 4. However, this should be allowed in tables.