fix: Remove [old] rtmp support

[dermotduffy]

• Requires at least Frigate 0.12 for rtsp support.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (946b2f0) to head (60888ed).
Report is 7 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff            @@
##            master      #776   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files           17        17           
  Lines         2023      2014    -9     
=========================================
- Hits          2023      2014    -9     

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[dermotduffy]

@felipecrs Mind taking a look at part 2? I set the cutoff to error >= v12, which is when rtmp support was first deprecated (since there was proper streaming!).

[felipecrs]

Maybe this should be kept as self._cam_name in self._frigate_config.get("go2rtc", {}).get("streams", {}).keys()?