This PR addresses a rounding error for 
`CompactNumberFormat.format(BigDecimal)`, which occurs when the maximum 
fraction digits value is greater than the minimum fraction digits value.

For example, given a format with 0 minimum fraction digits and 2 maximum 
fraction digits and a `BigDecimal` of 21_534_567.20, the following behavior 
occurs.

- `21_534_567.20` is first scaled to `21_534_567` to determine which compact 
divisor should be used
- The millions pattern is selected, and the following division occurs -> 
`21_534_567` / `1_000_000`. During the division operation, the minimum fraction 
digits is inherited as the scale and applied to the resulting quotient which 
produces 22.

Instead, the division should occur exactly, and `21_534_567` / `1_000_000`  
should produce `21.534567` which is then later rounded with the 2 maximum 
fraction digits to a value of `"21.53M"`.

While the filed regression points out the BD path, this also occurs for the BI 
formatting path when the underlying value is greater than what a `long` 
supports and whose division result would produce a fraction.

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- [x] I confirm that I make this contribution in accordance with the [OpenJDK 
Interim AI Policy](https://openjdk.org/legal/ai).

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Commit messages:
 - Cover BigInteger path
 - init

Changes: https://git.openjdk.org/jdk/pull/32933/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=32933&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8392400
  Stats: 41 lines in 2 files changed: 34 ins; 0 del; 7 mod
  Patch: https://git.openjdk.org/jdk/pull/32933.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/32933/head:pull/32933

PR: https://git.openjdk.org/jdk/pull/32933

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