Revert "Extend TransportSequenceNumber RTP header extension"

This reverts commit 28c7362bc485d22bdc8c744bc725022780187a96.

Reason for revert: It breaks Linux64 Release (libfuzzer):
https://logs.chromium.org/logs/webrtc/buildbucket/cr-buildbucket.appspot.com/8921003137877469920/+/steps/compile/0/stdout

Original change's description:
> Extend TransportSequenceNumber RTP header extension
> 
> Extend TransportSequenceNumber RTP header extension to support
> feedback on sender request.
> 
> Bug: webrtc:10262
> Change-Id: Ibc1cf18162d15cd102e951c9dc697d8ea536ebb6
> Reviewed-on: https://webrtc-review.googlesource.com/c/123233
> Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
> Reviewed-by: Alex Loiko <aleloi@webrtc.org>
> Commit-Queue: Johannes Kron <kron@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#26766}

TBR=danilchap@webrtc.org,aleloi@webrtc.org,kron@webrtc.org

Change-Id: Ie8a73f5fdffd99919ceaa1ae8911a1645f2077e9
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:10262
Reviewed-on: https://webrtc-review.googlesource.com/c/123522
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26767}

modules/rtp_rtcp/source/rtp_header_extension_map.cc

@@ -35,7 +35,6 @@ constexpr ExtensionInfo kExtensions[] = {
     CreateExtensionInfo<AbsoluteSendTime>(),
     CreateExtensionInfo<VideoOrientation>(),
     CreateExtensionInfo<TransportSequenceNumber>(),
-    CreateExtensionInfo<TransportSequenceNumberV2>(),
     CreateExtensionInfo<PlayoutDelayLimits>(),
     CreateExtensionInfo<VideoContentTypeExtension>(),
     CreateExtensionInfo<VideoTimingExtension>(),