attrs bump to 17.3

[iamnutzy1975]

Description of change

bump version of the dependent package called 'attrs' to 17.3

Manual QA steps

• pull data from facebook using this change and pull data from facebook without this change - compare

Rollback steps

• revert this branch

[cmerrick]

Hi @iamnutzy1975, thanks for your contribution!

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[cmerrick]

You did it @iamnutzy1975!

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