## Cause
dash auto dispose is configured by seconds, but the code compare by
usecond, 1 second = 1,000,000 useconds.
releated to #4097
Bug introduced after #4097 supported Dash auto dispose after a timeout
without media data.
## How to reproduce
1. `./objs/srs -c conf/dash.conf`
2. publish a rtmp stream.
3. play dash stream. -> no dash stream, always 404 error.
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Co-authored-by: winlin <winlinvip@gmail.com>
d220bf280e
