Simplify OutcomeResilienceStrategy

[martintmk]

Details on the issue fix or feature implementation

Just some code-cleanup and simplifications.

Confirm the following

• I started this PR by branching from the head of the default branch
• I have targeted the PR to merge into the default branch
• I have included unit tests for the issue/feature
• I have successfully run a local build

[codecov]

Codecov Report

Merging #1440 (b3caa61) into main (65df668) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #1440   +/-   ##
=======================================
  Coverage   83.94%   83.94%           
=======================================
  Files         276      276           
  Lines        6533     6533           
  Branches     1013     1013           
=======================================
  Hits         5484     5484           
  Misses        840      840           
  Partials      209      209           

Flag	Coverage Δ
linux	?
macos	83.94% <100.00%> (ø)
windows	83.94% <100.00%> (?)

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Files Changed	Coverage Δ
src/Polly.Core/Utils/OutcomeResilienceStrategy.cs	100.00% <100.00%> (ø)