[jdk17u-dev] RFR: 8293858: Change PKCS7 code to use default SecureRandom impl instead of SHA1PRNG

[Goetz Lindenmaier]

I backport this for parity with 17.0.8-oracle.

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Commit messages:
 - Backport 2157145766f9789ade0940e9ae1715a3b74d508b

Changes: https://git.openjdk.org/jdk17u-dev/pull/1284/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1284&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8293858
  Stats: 23 lines in 1 file changed: 1 ins; 19 del; 3 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1284.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1284/head:pull/1284

PR: https://git.openjdk.org/jdk17u-dev/pull/1284