The repeating group count check doesn't work if the count == 0

1) repro steps:
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send any message with valid repeating group fields except in the count, set the value to zero.

2) bad behavior:
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No error is thrown. the repeating group is not ignored and is parsed anyway even though the group count is zero. Note: i don't think fix protocol states how to handle this case but i would assume this is an error.

3) expected behavior:
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normally, if the count value doesn't match the actual number of "repeating group" you get this error: "Incorrect NumInGroup count for repeating group"