Fix parsing integer framerate. Release 1.0.1

[sgfn]

Passing a=framerate:30 in SDP raises.
Discovered during the workshop by an attendee who used the Meetecho WHIP client

16:05:25.267 [error] GenServer {Broadcaster.PeerRegistry, "8620e7f162"} terminating
** (ArgumentError) errors were found at the given arguments:

  * 1st argument: not a textual representation of a float

    :erlang.binary_to_float("30")
    (ex_sdp 1.0.0) lib/ex_sdp/attribute.ex:175: ExSDP.Attribute.parse_framerate/1
    (ex_sdp 1.0.0) lib/ex_sdp/media.ex:142: ExSDP.Media.parse_optional/2
    (ex_sdp 1.0.0) lib/ex_sdp/parser.ex:143: ExSDP.Parser.parse_line/2
    (ex_sdp 1.0.0) lib/ex_sdp/parser.ex:40: ExSDP.Parser.do_parse/2
    (ex_webrtc 0.4.0) lib/ex_webrtc/peer_connection.ex:1560: ExWebRTC.PeerConnection.parse_sdp/1
    (ex_webrtc 0.4.0) lib/ex_webrtc/peer_connection.ex:1400: ExWebRTC.PeerConnection.apply_remote_description/2
    (ex_webrtc 0.4.0) lib/ex_webrtc/peer_connection.ex:650: ExWebRTC.PeerConnection.handle_call/3
Last message (from #PID<0.1889.0>): {:set_remote_description, %ExWebRTC.SessionDescription{type: :offer, sdp: "v=0\r\no=- 8997921153665821411 0 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=ice-options:trickle\r\na=group:BUNDLE video0 audio1\r\nm=video 9 UDP/TLS/RTP/SAVPF 96\r\nc=IN IP4 0.0.0.0\r\na=setup:actpass\r\na=ice-ufrag:bzlfqm6/vblska6CMDh4gYbyib/dCNGd\r\na=ice-pwd:txT29m+eAgy/czZOjWgXzbz8WyU0IZdX\r\na=rtcp-mux\r\na=rtcp-rsize\r\na=sendrecv\r\na=rtpmap:96 VP8/90000\r\na=rtcp-fb:96 nack pli\r\na=rtcp-fb:96 transport-cc\r\na=framerate:30\r\na=ssrc:2 msid:user558725149@host-a208fcce webrtctransceiver0\r\na=ssrc:2 cname:user558725149@host-a208fcce\r\na=mid:video0\r\na=fingerprint:sha-256 C2:56:EA:3E:E2:7A:0C:08:8F:FC:45:92:BF:44:09:88:96:7C:FE:77:90:A1:52:F4:F7:EE:E5:32:FC:C6:DE:54\r\na=rtcp-mux-only\r\nm=audio 0 UDP/TLS/RTP/SAVPF 100\r\nc=IN IP4 0.0.0.0\r\na=setup:actpass\r\na=ice-ufrag:bzlfqm6/vblska6CMDh4gYbyib/dCNGd\r\na=ice-pwd:txT29m+eAgy/czZOjWgXzbz8WyU0IZdX\r\na=bundle-only\r\na=rtcp-mux\r\na=rtcp-rsize\r\na=sendrecv\r\na=rtpmap:100 OPUS/48000/2\r\na=rtcp-fb:100 transport-cc\r\na=fmtp:100 sprop-stereo=0;sprop-maxcapturerate=48000\r\na=ssrc:1 msid:user558725149@host-a208fcce webrtctransceiver1\r\na=ssrc:1 cname:user558725149@host-a208fcce\r\na=mid:audio1\r\na=fingerprint:sha-256 C2:56:EA:3E:E2:7A:0C:08:8F:FC:45:92:BF:44:09:88:96:7C:FE:77:90:A1:52:F4:F7:EE:E5:32:FC:C6:DE:54\r\na=rtcp-mux-only\r\n"}}
16:05:25.267 request_id=F_Q1oYhecVLFojIAAD8C [error] GenServer #PID<0.1889.0> terminating
** (stop) exited in: GenServer.call(#PID<0.1890.0>, {:set_remote_description, %ExWebRTC.SessionDescription{type: :offer, sdp: "v=0\r\no=- 8997921153665821411 0 IN IP4 0.0.0.0\r\ns=-\r\nt=0 0\r\na=ice-options:trickle\r\na=group:BUNDLE video0 audio1\r\nm=video 9 UDP/TLS/RTP/SAVPF 96\r\nc=IN IP4 0.0.0.0\r\na=setup:actpass\r\na=ice-ufrag:bzlfqm6/vblska6CMDh4gYbyib/dCNGd\r\na=ice-pwd:txT29m+eAgy/czZOjWgXzbz8WyU0IZdX\r\na=rtcp-mux\r\na=rtcp-rsize\r\na=sendrecv\r\na=rtpmap:96 VP8/90000\r\na=rtcp-fb:96 nack pli\r\na=rtcp-fb:96 transport-cc\r\na=framerate:30\r\na=ssrc:2 msid:user558725149@host-a208fcce webrtctransceiver0\r\na=ssrc:2 cname:user558725149@host-a208fcce\r\na=mid:video0\r\na=fingerprint:sha-256 C2:56:EA:3E:E2:7A:0C:08:8F:FC:45:92:BF:44:09:88:96:7C:FE:77:90:A1:52:F4:F7:EE:E5:32:FC:C6:DE:54\r\na=rtcp-mux-only\r\nm=audio 0 UDP/TLS/RTP/SAVPF 100\r\nc=IN IP4 0.0.0.0\r\na=setup:actpass\r\na=ice-ufrag:bzlfqm6/vblska6CMDh4gYbyib/dCNGd\r\na=ice-pwd:txT29m+eAgy/czZOjWgXzbz8WyU0IZdX\r\na=bundle-only\r\na=rtcp-mux\r\na=rtcp-rsize\r\na=sendrecv\r\na=rtpmap:100 OPUS/48000/2\r\na=rtcp-fb:100 transport-cc\r\na=fmtp:100 sprop-stereo=0;sprop-maxcapturerate=48000\r\na=ssrc:1 msid:user558725149@host-a208fcce webrtctransceiver1\r\na=ssrc:1 cname:user558725149@host-a208fcce\r\na=mid:audio1\r\na=fingerprint:sha-256 C2:56:EA:3E:E2:7A:0C:08:8F:FC:45:92:BF:44:09:88:96:7C:FE:77:90:A1:52:F4:F7:EE:E5:32:FC:C6:DE:54\r\na=rtcp-mux-only\r\n"}}, 5000)