Prevent ConcurrentModificationException when reading feature flags

[0xnm]

What does this PR do?

Small change to prevent ConcurrentModificationException which may happen when feature flags are read during ErrorEvent serialization on the worker thread.

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• Make sure you discussed the feature or bugfix with the maintaining team in an Issue
• Make sure each commit and the PR mention the Issue number (cf the CONTRIBUTING doc)

[codecov-commenter]

Codecov Report

Merging #1925 (e47a102) into develop (12e4b09) will increase coverage by 0.05%.
The diff coverage is 100.00%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1925      +/-   ##
===========================================
+ Coverage    83.34%   83.39%   +0.05%     
===========================================
  Files          481      481              
  Lines        17408    17398      -10     
  Branches      2589     2588       -1     
===========================================
  Hits         14508    14508              
+ Misses        2193     2182      -11     
- Partials       707      708       +1     

Files	Coverage Δ
.../android/rum/internal/domain/scope/RumViewScope.kt	93.36% <100.00%> (+0.01%)	⬆️

... and 25 files with indirect coverage changes

[xgouchet]

Nice work, do you think you can add a Unit Test to verify we don't remove this in the future?

[0xnm]

@xgouchet Good idea! I will do it then in another PR, because I want this change to be shipped with upcoming release.