docs(README): list app flavours

[vitorhugods]

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PR Submission Checklist for internal contributors

• The PR Title

  • conforms to the style of semantic commits messages¹ supported in Wire's Github Workflow²
  • answers the question: If merged, this PR will: ... ³

• The PR Description

  • is free of optional paragraphs and you have filled the relevant parts to the best of your ability

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What's new in this PR?

Issues

What are build flavours??

Causes

Too many, idk.

Solutions

Explain what they are, what they do, what they think, who's their favourite pop singer, if they care about cappuccino after 11AM or not.

Testing

N/A

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PR Post Merge Checklist for internal contributors

• If any soft of configuration variable was introduced by this PR, it has been added to the relevant documents and the CI jobs have been updated.

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References

1. https://sparkbox.com/foundry/semantic_commit_messages
2. https://github.com/wireapp/.github#usage
3. E.g. feat(conversation-list): Sort conversations by most emojis in the title #SQPIT-764.

[github-actions]

Test Results

821 tests   821 ✅  9m 25s ⏱️
114 suites    0 💤
114 files      0 ❌

Results for commit 56e9f53.

♻️ This comment has been updated with latest results.

[AndroidBob]

Build 3296 failed.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 43.07%. Comparing base (0e0430d) to head (56e9f53).
Report is 3 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #2735      +/-   ##
===========================================
- Coverage    43.08%   43.07%   -0.01%     
===========================================
  Files          408      408              
  Lines        13523    13521       -2     
  Branches      2390     2389       -1     
===========================================
- Hits          5826     5824       -2     
  Misses        7014     7014              
  Partials       683      683              

see 1 file with indirect coverage changes

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[github-actions]

APKs built during tests are available here. Scroll down to Artifacts!

[AndroidBob]

Build 3300 succeeded.

The build produced the following APK's:

• com.wire.android-v4.7.0(8972344)(8972344)-staging-compat.apk