[jdk21u-dev] RFR: 8349151: Refactor test/java/security/cert/CertificateFactory/slowstream.sh to java test

[Goetz Lindenmaier]

I backport this for parity with 21.0.9-oracle.

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Commit messages:
 - Backport fbc12be73217315d66792b6ad3faacab133bb9d5

Changes: https://git.openjdk.org/jdk21u-dev/pull/1984/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1984&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8349151
  Stats: 122 lines in 2 files changed: 47 ins; 58 del; 17 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1984.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1984/head:pull/1984

PR: https://git.openjdk.org/jdk21u-dev/pull/1984