File breaking change related to Japanese Meiji era start date

[richlander]

This is low-pri tracking issue (not because of the topic, because of the holidays), for filing a breaking change and deciding on our backporting approach.

• Support ICU v78 changes including IDN and Japanese Meiji era start date #122480

.NET 8+ will definitely be running with this new ICU and or Ubuntu 26.04. We'll need to decide on this so that we don't have to post a known issue when 26.04 ships (April).

@tarekgh @jeffhandley @dviererbe @lbussell

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[tarekgh]

The breaking change doc is filed: dotnet/docs#50894