docs : Added snap insallation proccess

[MrSIHAB]

Snap is more simple and better way to install flutter. It's a good solution for beginners to advace user.

[github-actions]

No release type found in pull request title "docs : Added snap insallation proccess". Add a prefix to indicate what kind of release this pull request corresponds to. For reference, see https://www.conventionalcommits.org/

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[Feichtmeier]

hi! yes this would be our desired way too, however due to our apps modifying the myapplication.cc with native libraries this does not work well, this is why we do not recommend it for desktop installations (currently)