[jdk21u-dev] RFR: 8319174: Enhance robustness of some j.m.BigInteger constructors

[Goetz Lindenmaier]

I backport this for parity with 21.0.9-oracle

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Commit messages:
 - Backport a64fc48e2dbc650b31869dd79b1ba1012376fc51

Changes: https://git.openjdk.org/jdk21u-dev/pull/1990/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1990&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8319174
  Stats: 323 lines in 3 files changed: 253 ins; 7 del; 63 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1990.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1990/head:pull/1990

PR: https://git.openjdk.org/jdk21u-dev/pull/1990