Update module github.com/pion/rtp to v1.8.21

Generated by renovateBot

Author: renovate[bot]

go.mod

@@ -15,7 +15,7 @@ require (
 	github.com/pion/interceptor v0.1.40
 	github.com/pion/logging v0.2.4
 	github.com/pion/rtcp v1.2.15
-	github.com/pion/rtp v1.8.20
+	github.com/pion/rtp v1.8.21
 	github.com/pion/sdp/v3 v3.0.15
 	github.com/pion/webrtc/v4 v4.1.3
 	gocv.io/x/gocv v0.40.0

go.sum

@@ -46,8 +46,8 @@ github.com/pion/randutil v0.1.0 h1:CFG1UdESneORglEsnimhUjf33Rwjubwj6xfiOXBa3mA=
 github.com/pion/randutil v0.1.0/go.mod h1:XcJrSMMbbMRhASFVOlj/5hQial/Y8oH/HVo7TBZq+j8=
 github.com/pion/rtcp v1.2.15 h1:LZQi2JbdipLOj4eBjK4wlVoQWfrZbh3Q6eHtWtJBZBo=
 github.com/pion/rtcp v1.2.15/go.mod h1:jlGuAjHMEXwMUHK78RgX0UmEJFV4zUKOFHR7OP+D3D0=
-github.com/pion/rtp v1.8.20 h1:8zcyqohadZE8FCBeGdyEvHiclPIezcwRQH9zfapFyYI=
-github.com/pion/rtp v1.8.20/go.mod h1:bAu2UFKScgzyFqvUKmbvzSdPr+NGbZtv6UB2hesqXBk=
+github.com/pion/rtp v1.8.21 h1:3yrOwmZFyUpcIosNcWRpQaU+UXIJ6yxLuJ8Bx0mw37Y=
+github.com/pion/rtp v1.8.21/go.mod h1:bAu2UFKScgzyFqvUKmbvzSdPr+NGbZtv6UB2hesqXBk=
 github.com/pion/sctp v1.8.39 h1:PJma40vRHa3UTO3C4MyeJDQ+KIobVYRZQZ0Nt7SjQnE=
 github.com/pion/sctp v1.8.39/go.mod h1:cNiLdchXra8fHQwmIoqw0MbLLMs+f7uQ+dGMG2gWebE=
 github.com/pion/sdp/v3 v3.0.15 h1:F0I1zds+K/+37ZrzdADmx2Q44OFDOPRLhPnNTaUX9hk=