RFR: 8232838: Update VerifyCACerts test to ensure cacerts contain entries for CA

[Rajan Halade]

Updated VerifyCACerts test to check if BasicConstraints lists "CA:true" and KeyUsage, if included, asserts the keyCertSign bit.

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Commit messages:
 - 8232838: Update VerifyCACerts test to ensure cacerts contain entries for CA

Changes: https://git.openjdk.org/jdk/pull/20573/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20573&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8232838
  Stats: 18 lines in 1 file changed: 15 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/20573.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20573/head:pull/20573

PR: https://git.openjdk.org/jdk/pull/20573