Fix Transport-wide RTCP Feedback Message parsing

[moninom1]

Issue #, if available:
The TWCC RTCP feedback message - Status Vector Chunk parsing was extracting incorrect symbol list.
Reference for parsing.

Currently parsed output :

packetChunk 58709 [0xe555]
1[chunk type] 1[symbol size] 10 01 01 01 01 01 01

Incorrect statusVector statusSymbol read - 2, 2, 0, 0, 0, 0, 0

Expected Output :

packetChunk 58709 [0xe555]
1[chunk type] 1[symbol size] 10 01 01 01 01 01 01

statusVector statusSymbol read - 2, 1, 1, 1, 1, 1, 1

What was changed?
Updated the packet parsing.

Why was it changed?
It is updated for correct packet chunk parsing.

How was it changed?
The mask used for extracting status symbol is updated along with the position from where the bits need to be read.

What testing was done for the changes?
Verified by running demo & printing the output of packet vector chunk being parsed correctly.
Output with the change :

packetChunk 58709 [0xe555]
1[chunk type] 1[symbol size] 10 01 01 01 01 01 01

statusVector statusSymbol read - 2, 1, 1, 1, 1, 1, 1

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[hassanctech]

Good find!