icu4c 75.1

[cho-m]

Created with brew bump-formula-pr.

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Major changes

This release introduces C++17 minimum which impacts various dependents.

Versioning attempt

As reference:

• Previous bump - #153108
• CI runtime: https://github.com/Homebrew/homebrew-core/actions/runs/8007761525/usage (2d 6h Intel macOS, 1d 17hr Linux)

May try versioning approach and test largest dep group to see if it improves anything.

EDIT: The largest connected deps group means at least 42 formulae need to be migrated on macOS (more if including Linux due to libxml2 and other common dependencies).