Location sharing - extract isSelfLocation util

[kerryarchibald]

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This change is marked as an internal change (Task), so will not be included in the changelog.

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[codecov]

Codecov Report

Merging #8279 (2b8f7fc) into develop (61076c3) will increase coverage by 0.17%.
The diff coverage is 93.85%.

@@             Coverage Diff             @@
##           develop    #8279      +/-   ##
===========================================
+ Coverage    29.25%   29.43%   +0.17%     
===========================================
  Files          863      867       +4     
  Lines        49876    49953      +77     
  Branches     12696    12708      +12     
===========================================
+ Hits         14592    14702     +110     
+ Misses       35284    35251      -33     

Impacted Files	Coverage Δ
...c/components/views/location/LocationViewDialog.tsx	0.00% <0.00%> (ø)
src/TextForEvent.tsx	43.85% <80.00%> (+8.11%)	⬆️
src/utils/location/map.ts	85.71% <88.23%> (-14.29%)	⬇️
src/components/views/location/Marker.tsx	100.00% <100.00%> (ø)
src/components/views/location/SmartMarker.tsx	100.00% <100.00%> (ø)
src/components/views/location/ZoomButtons.tsx	100.00% <100.00%> (ø)
src/components/views/messages/MBeaconBody.tsx	100.00% <100.00%> (+92.85%)	⬆️
src/components/views/messages/MLocationBody.tsx	68.00% <100.00%> (-2.38%)	⬇️
src/components/views/messages/MessageEvent.tsx	62.26% <100.00%> (ø)
src/stores/OwnBeaconStore.ts	97.84% <100.00%> (+1.11%)	⬆️
... and 6 more