Disable preferSwiftStringAPI by default due to iOS 16 / macOS 13 API availability

[calda]

replacing(_:with:) is only available on iOS 16+ / macOS 13+. For example, the SwiftFormat codebase no longer compiles when the rule is applied, since the minimum macOS version is 10.14.

Eventually we could add something like --apple-os-version 26 that would let us have these sorts of things be enabled by default, but gated behind OS version like how we gate functionality by Swift version. The unified 26.0 / 27.0 version numbers will make this easy eventually but for now it's still a bit tricky.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.30%. Comparing base (08e0f66) to head (b7fd609).
⚠️ Report is 2 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #2495   +/-   ##
========================================
  Coverage    95.30%   95.30%           
========================================
  Files          168      168           
  Lines        25383    25383           
========================================
+ Hits         24191    24192    +1     
+ Misses        1192     1191    -1     

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