More robust handling of userAgentData, fix WebPushDeviceAdmin

[simonkern]

Relevant userAgentData ist not always stored in navigator.userAgentData.brands[0]

It is necessary to loop through all available navigator.userAgentData.brands and try to find the relevant entry. In case of Edge (and maybe in case of other chromium-based browsers too) it is also necessary to ignore any matches regarding chrome...

addresses #640

[codecov[bot]]

Codecov Report

Merging #643 (c88d5fe) into master (56995b1) will decrease coverage by 0.00%. The diff coverage is 71.42%.

@@            Coverage Diff             @@
##           master     #643      +/-   ##
==========================================
- Coverage   68.33%   68.32%   -0.01%     
==========================================
  Files          25       25              
  Lines        1102     1108       +6     
  Branches      240      242       +2     
==========================================
+ Hits          753      757       +4     
- Misses        312      313       +1     
- Partials       37       38       +1     

Impacted Files	Coverage Δ
push_notifications/admin.py	34.69% <71.42%> (+2.08%)	:arrow_up:

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[simonkern]

Field "device_id" is not available for WebPushDevices. Instead I added "browser" to ListView and "registration_id" to search_fields, by Subclassing DeviceAdmin for WebpushDevice.

[simonkern]

@auvipy what do you have in mind? Except for the field changes in the broken admin, these are only changes to the README.

[auvipy]

@dismine

[dismine]

New function loadVersionBrowser works for me. Already ported to my website.