gst-plugins-rs: update for gst-plugin-webrtc feature rename

See gst-plugins-rs!1241 (merged)

---

Build failure in nightly pipeline:

Running command ['/private/tmp/builds/gstreamer/cerbero/cerbero-build/rust/cargo/bin/cargo', 'cbuild', '--release', '--frozen', '--prefix', '/private/tmp/builds/gstreamer/cerbero/cerbero-build/dist/darwin_universal/arm64', '--libdir', '/private/tmp/builds/gstreamer/cerbero/cerbero-build/dist/darwin_universal/arm64/lib', '--library-type', 'cdylib', '--verbose', '--offline', '--target', 'aarch64-apple-darwin', '--target-dir', '/private/tmp/builds/gstreamer/cerbero/cerbero-build/sources/darwin_universal/arm64/gst-plugins-rs-0.12.0-alpha.1/_builddir', '-j18', '-p', 'gst-plugin-audiofx', '-p', 'gst-plugin-aws', '-p', 'gst-plugin-cdg', '-p', 'gst-plugin-claxon', '-p', 'gst-plugin-closedcaption', '-p', 'gst-plugin-dav1d', '-p', 'gst-plugin-fallbackswitch', '-p', 'gst-plugin-ffv1', '-p', 'gst-plugin-fmp4', '-p', 'gst-plugin-gif', '-p', 'gst-plugin-hlssink3', '-p', 'gst-plugin-hsv', '-p', 'gst-plugin-json', '-p', 'gst-plugin-livesync', '-p', 'gst-plugin-lewton', '-p', 'gst-plugin-mp4', '-p', 'gst-plugin-ndi', '-p', 'gst-plugin-onvif', '-p', 'gst-plugin-rav1e', '-p', 'gst-plugin-regex', '-p', 'gst-plugin-reqwest', '-p', 'gst-plugin-raptorq', '-p', 'gst-plugin-png', '-p', 'gst-plugin-rtp', '-p', 'gst-plugin-textahead', '-p', 'gst-plugin-textwrap', '-p', 'gst-plugin-threadshare', '-p', 'gst-plugin-togglerecord', '-p', 'gst-plugin-tracers', '-p', 'gst-plugin-uriplaylistbin', '-p', 'gst-plugin-videofx', '-p', 'gst-plugin-webrtc', '-p', 'gst-plugin-webrtchttp', '--features=glib/v2_74,gio/v2_74,gst-plugin-rav1e/asm,gst/v1_22,gst-app/v1_22,gst-audio/v1_22,gst-base/v1_22,gst-check/v1_22,gst-net/v1_22,gst-pbutils/v1_22,gst-plugin-tracers/v1_22,gst-rtp/v1_22,gst-sdp/v1_22,gst-utils/v1_22,gst-video/v1_22,gst-webrtc/v1_22,gst-plugin-webrtc/gst1_22'] in /private/tmp/builds/gstreamer/cerbero/cerbero-build/sources/darwin_universal/arm64/gst-plugins-rs-0.12.0-alpha.1/_builddir
Error: CliError { error: Some(none of the selected packages contains these features: gst-plugin-webrtc/gst1_22, did you mean: gst-plugin-webrtc/v1_22?), exit_code: 101 }
2024/02/02 05:37:10 Process exited with status 1`