webrtcbin test: Fix race in new test
Pull a buffer from a sink to make sure that the caps are already set before trying to update them.
This was discovered by our CI: https://gitlab.freedesktop.org/ocrete/gst-plugins-bad/-/jobs/9856100
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Pull a buffer from a sink to make sure that the caps are already set before trying to update them.
This was discovered by our CI: https://gitlab.freedesktop.org/ocrete/gst-plugins-bad/-/jobs/9856100