RFR: 8299746: Accept unknown signatureAlgorithm in PKCS7 SignerInfo

[Weijun Wang]

Modern signature algorithms provided by a 3rd-party provider might not be recognized by JDK code yet.

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Commit messages:
 - the fix

Changes: https://git.openjdk.org/jdk/pull/11883/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11883&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8299746
  Stats: 62 lines in 2 files changed: 60 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/11883.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11883/head:pull/11883

PR: https://git.openjdk.org/jdk/pull/11883