[docs] [issue31942] Document that support of start and stop parameters in the Sequence's index() is optional

[Serhiy Storchaka]

Change by Serhiy Storchaka <storchaka+cpython at gmail.com>:


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nosy: +Devin Jeanpierre

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue31942>
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