RTSP: Support absolute timing

### ExoPlayer Version

2.18.1

### Devices that reproduce the issue

Motorola Moto g30 Android 12

### Devices that do not reproduce the issue

_No response_

### Reproducible in the demo app?

Yes

### Reproduction steps

When I reproduce this uri of a hikvision ip camera, the reproduction does not give me any problem:
rtsp://xxx:xxx@host:port/ISAPI/Streaming/Channels/301

but if i try to play with this uri (which worked ok in vlc and other libraries):
rtsp://xxx:xxx@host:port/ISAPI/Streaming/tracks/301?starttime=20221121T073315Z

it gives me the following error:

2022-11-22 11:40:21.832 4783-4850/com.example.tssexoprueba E/ExoPlayerImplInternal: Playback error
com.google.android.exoplayer2.ExoPlaybackException: Source error
at com.google.android.exoplayer2.ExoPlayerImplInternal.handleIoException(ExoPlayerImplInternal.java:632)
at com.google.android.exoplayer2.ExoPlayerImplInternal.handleMessage(ExoPlayerImplInternal.java:608)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loopOnce(Looper.java:226)
at android.os.Looper.loop(Looper.java:329)
at android.os.HandlerThread.run(HandlerThread.java:67)
Caused by: java.io.IOException: SDP format error.
at com.google.android.exoplayer2.source.rtsp.RtspMediaPeriod$InternalListener.onSessionTimelineRequestFailed(RtspMediaPeriod.java:652)
at com.google.android.exoplayer2.source.rtsp.RtspClient$MessageListener.onDescribeResponseReceived(RtspClient.java:685)
at com.google.android.exoplayer2.source.rtsp.RtspClient$MessageListener.handleRtspResponse(RtspClient.java:598)
at com.google.android.exoplayer2.source.rtsp.RtspClient$MessageListener.handleRtspMessage(RtspClient.java:507)
at com.google.android.exoplayer2.source.rtsp.RtspClient$MessageListener.lambda$onRtspMessageReceived$0$com-google-android-exoplayer2-source-rtsp-RtspClient$MessageListener(RtspClient.java:500)
at com.google.android.exoplayer2.source.rtsp.RtspClient$MessageListener$$ExternalSyntheticLambda0.run(Unknown Source:4)
at android.os.Handler.handleCallback(Handler.java:938)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loopOnce(Looper.java:226) 
at android.os.Looper.loop(Looper.java:329) 
at android.os.HandlerThread.run(HandlerThread.java:67) 
Caused by: com.google.android.exoplayer2.ParserException: clock=20221121T073315Z-20221122T113914Z
at com.google.android.exoplayer2.source.rtsp.RtspMessageUtil.checkManifestExpression(RtspMessageUtil.java:471)
at com.google.android.exoplayer2.source.rtsp.RtspSessionTiming.parseTiming(RtspSessionTiming.java:51)
at com.google.android.exoplayer2.source.rtsp.RtspClient$MessageListener.onDescribeResponseReceived(RtspClient.java:683)
at com.google.android.exoplayer2.source.rtsp.RtspClient$MessageListener.handleRtspResponse(RtspClient.java:598) 
at com.google.android.exoplayer2.source.rtsp.RtspClient$MessageListener.handleRtspMessage(RtspClient.java:507) 
at com.google.android.exoplayer2.source.rtsp.RtspClient$MessageListener.lambda$onRtspMessageReceived$0$com-google-android-exoplayer2-source-rtsp-RtspClient$MessageListener(RtspClient.java:500) 
at com.google.android.exoplayer2.source.rtsp.RtspClient$MessageListener$$ExternalSyntheticLambda0.run(Unknown Source:4) 
at android.os.Handler.handleCallback(Handler.java:938) 
at android.os.Handler.dispatchMessage(Handler.java:99) 
at android.os.Looper.loopOnce(Looper.java:226) 
at android.os.Looper.loop(Looper.java:329) 
at android.os.HandlerThread.run(HandlerThread.java:67) 

### Expected result

The media plays ok

### Actual result

it gives me an error

### Media

Not applicable

### Bug Report

- [X] You will email the zip file produced by `adb bugreport` to dev.exoplayer@gmail.com after filing this issue.