Add the EUSM Burundi flavour and Rename the existing EUSM flavour

[dubdabasoduba]

• Rename the exisiting EUSM flavour

IMPORTANT: Where possible all PRs must be linked to a Github issue

Fixes [link to issue]

Engineer Checklist

• I have written Unit tests for any new feature(s) and edge cases for bug fixes
• I have added any strings visible on UI components to the strings.xml file
• I have updated the CHANGELOG.md file for any notable changes to the codebase
• I have run ./gradlew spotlessApply and ./gradlew spotlessCheck to check my code follows the project's style guide
• I have built and run the FHIRCore app to verify my change fixes the issue and/or does not break the app
• I have checked that this PR does NOT introduce breaking changes that require an update to Content and/or Configs? If it does add a sample here or a link to exactly what changes need to be made to the content.

Code Reviewer Checklist

• I have verified Unit tests have been written for any new feature(s) and edge cases
• I have verified any strings visible on UI components are in the strings.xml file
• I have verifed the CHANGELOG.md file has any notable changes to the codebase
• I have verified the solution has been implemented in a configurable and generic way for reuseable components
• I have built and run the FHIRCore app to verify the change fixes the issue and/or does not break the app

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 27.2%. Comparing base (8cf03cf) to head (5c9d907).
Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##              main   #3548   +/-   ##
=======================================
  Coverage     27.2%   27.2%           
  Complexity     756     756           
=======================================
  Files          278     278           
  Lines        14219   14218    -1     
  Branches      2581    2581           
=======================================
  Hits          3880    3880           
+ Misses        9801    9800    -1     
  Partials       538     538           

Flag	Coverage Δ
engine	63.8% <ø> (ø)
geowidget	15.4% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

[dubdabasoduba]

@ndegwamartin @ellykits DId we ever agree on how to name these? Are we using underscores or camel case