Fixed message update in channel state

[AnatolyRugalev]

There's a regression after we introduced own_reactions sync to ChannelState. This PR fixes it and simplifies some reaction-related code

[github-actions]

Size Change: -333 B (0%)

Total Size: 211 kB

Filename	Size	Change
dist/browser.es.js	45.8 kB	-75 B (0%)
dist/browser.full-bundle.min.js	27 kB	-27 B (0%)
dist/browser.js	46.4 kB	-76 B (0%)
dist/index.es.js	45.9 kB	-76 B (0%)
dist/index.js	46.4 kB	-79 B (0%)

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