videoservice: Fix handling streams w/o codec_type

Some streams do not have a 'codec_type', which throws the following
traceback:

> File "/usr/bin/vidcutter", line 11, in <module>
>   load_entry_point('vidcutter==6.0.0', 'gui_scripts', 'vidcutter')()
> File "/usr/lib/python3/dist-packages/vidcutter/__main__.py", line 380, in main
>   win = MainWindow()
> File "/usr/lib/python3/dist-packages/vidcutter/__main__.py", line 86, in __init__
>   self.file_opener(self.video)
> File "/usr/lib/python3/dist-packages/vidcutter/__main__.py", line 102, in file_opener
>   self.cutter.loadMedia(filename)
> File "/usr/lib/python3/dist-packages/vidcutter/videocutter.py", line 988, in loadMedia
>   self.videoService.setMedia(self.currentMedia)
> File "/usr/lib/python3/dist-packages/vidcutter/libs/videoservice.py", line 93, in setMedia
>   [stream for stream in self.media.streams if stream.codec_type == codec_type.lower()])
> File "/usr/lib/python3/dist-packages/vidcutter/libs/videoservice.py", line 93, in <listcomp>
>   [stream for stream in self.media.streams if stream.codec_type == codec_type.lower()])
> File "/usr/lib/python3/dist-packages/vidcutter/libs/munch.py", line 104, in __getattr__
>   raise AttributeError(k)

The output of
    ffprobe -hide_banner -v error -show_streams -show_format -of json $FILE.mpg
looks like this:

> {
>     "streams": [
>     ...
>         {
>             "index": 8,
>             "codec_tag_string": "[5][0][0][0]",
>             "codec_tag": "0x0005",
>             "id": "0x181a",
>             "r_frame_rate": "0/0",
>             "avg_frame_rate": "0/0",
>             "time_base": "1/90000",
>             "start_pts": 873142304,
>             "start_time": "9701.581156",
>             "duration_ts": 685844313,
>             "duration": "7620.492367",
>             "disposition": {
>                 "default": 0,
>                 "dub": 0,
>                 "original": 0,
>                 "comment": 0,
>                 "lyrics": 0,
>                 "karaoke": 0,
>                 "forced": 0,
>                 "hearing_impaired": 0,
>                 "visual_impaired": 0,
>                 "clean_effects": 0,
>                 "attached_pic": 0,
>                 "timed_thumbnails": 0
>             }
>         }
> ...
> ]}

This is a DVB-C recording, which consists of 1 video stream, multiple
audio- and subtext-streams, and that strange "data" stream.

Similar to <ozmartian#203>
Fixes: <ozmartian#211>

Author: pmhahn

vidcutter/libs/videoservice.py

@@ -90,7 +90,7 @@ def setMedia(self, source: str) -> None:
                     self.logger.info(self.media)
                 for codec_type in Streams.__members__:
                     setattr(self.streams, codec_type.lower(),
-                            [stream for stream in self.media.streams if stream.codec_type == codec_type.lower()])
+                            [stream for stream in self.media.streams if stream.get('codec_type') == codec_type.lower()])
                 if len(self.streams.video):
                     self.streams.video = self.streams.video[0]  # we always assume one video stream per media file
                 else: