Don't cancel cache flushing on init

[Tyrrrz]

Closes #1071

[codecov-commenter]

Codecov Report

Merging #1139 (c16606c) into main (46bcd9f) will decrease coverage by 1.46%.
The diff coverage is 27.27%.

@@            Coverage Diff             @@
##             main    #1139      +/-   ##
==========================================
- Coverage   80.75%   79.29%   -1.47%     
==========================================
  Files         200      200              
  Lines        6615     6617       +2     
  Branches     1464     1465       +1     
==========================================
- Hits         5342     5247      -95     
- Misses        802      908     +106     
+ Partials      471      462       -9     

Impacted Files	Coverage Δ
src/Sentry/Internal/SdkComposer.cs	42.22% <27.27%> (+5.01%)	⬆️
src/Sentry/PlatformAbstractions/FrameworkInfo.cs	0.00% <0.00%> (-100.00%)	⬇️
...ntry/PlatformAbstractions/RegistryKeyExtensions.cs	0.00% <0.00%> (-100.00%)	⬇️
...Sentry/PlatformAbstractions/FrameworkInfo.NetFx.cs	0.00% <0.00%> (-70.43%)	⬇️
...rmAbstractions/NetFxInstallationsEventProcessor.cs	4.54% <0.00%> (-68.19%)	⬇️
...ntry/PlatformAbstractions/FrameworkInstallation.cs	25.00% <0.00%> (-37.50%)	⬇️
...ntry/Integrations/NetFxInstallationsIntegration.cs	28.57% <0.00%> (-28.58%)	⬇️
src/Sentry/PlatformAbstractions/RuntimeInfo.cs	54.23% <0.00%> (-5.09%)	⬇️
src/Sentry/Internal/AppDomainAdapter.cs	66.66% <0.00%> (ø)
... and 1 more

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[bruno-garcia]

As discussed on the call best to inline the logic and avoid the task cancelled exxception then