Fix Style/OperatorMethodCall autocorrection when operators are chained

[gsamokovarov]

Ran it in Dext and this little gem of a code...

receipt_total = receipt.total_amount.*(convert_rate).round(2)
receipt_vat = receipt.tax_amount.*(convert_rate).round(2)

got autocorrected to:

receipt_total = receipt.total_amount(*convert_rate.round(2))
receipt_vat = receipt.tax_amount(*convert_rate.round(2))

I expected:

receipt_total = (receipt.total_amount * convert_rate).round(2)
receipt_vat = (receipt.tax_amount * convert_rate).round(2)

The Style/OperatorMethodCall didn't autocorrect operator method calls in chaining properly so I made it so.

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[koic]

Thanks!