Update ICU4J NumberRegression.

In a recent change to android.icu.DecimalFormat we increased the maximum
integer digits to 2 billion to be consistent with the ICU4C
implementation and support java.text.DecimalFormat.

This change updates the serialization regression test to coincide with
that chage.

Bug: 28397841
Bug: 27855939

(cherry picked from commit b6fbe956afc8bf4c8e47fc2e6ce6680f6043ba7b)

Change-Id: I154d23612f4dadf07ea918c739aa54597c22cc76
2 files changed