Generalize UT of RateGroupDriver

[SMorettini]

Has Unit Tests (y/n)
Documentation Included (y/n)

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Change Description

The UT of RateGroupDriver was failing if RateGroupDriverRateGroupPorts in AcConstant.fpp was different from 3. The new change makes the test work for any value.

[LeStarch]

I switched the use of int (signed) to the used of FwIndexType that is the expected type to represent such things (i.e. port indices). Hope you don't mind the assistance, figured it was easier than the back-and-forth for such a small delta. Thanks for this correction, it will help substantially!

[SMorettini]

@LeStarch thanks for the fix. It still doesn't pass the CI, I wanted to solve it but I don't know if you prefer casting the DIVIDER_SIZE or change the type of i

[LeStarch]

@SMorettini in this case, I'd cast it.