RFR: 8373068: Revisit details of Float16 to decimal conversion algorithm

[Raffaello Giulietti]

Change the range for plain notation, reducing it to the interval [1e-3, 1e3).

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Commit messages:
 - 8373068: Revisit details of Float16 to decimal conversion algorithm

Changes: https://git.openjdk.org/jdk/pull/28875/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28875&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8373068
  Stats: 4 lines in 1 file changed: 3 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/28875.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28875/head:pull/28875

PR: https://git.openjdk.org/jdk/pull/28875