[jdk16u] RFR: 8196415: Disable SHA-1 Signed JARs

[Prajwal Kumaraswamy]

This is a clean backport.
I've ran this against test suite and works fine.

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Commit messages:
 - Backport 278057756a1a79a4b030750c48b821ba9735a0f9

Changes: https://git.openjdk.java.net/jdk16u/pull/111/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk16u&pr=111&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8196415
  Stats: 3 lines in 1 file changed: 1 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk16u/pull/111.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk16u pull/111/head:pull/111

PR: https://git.openjdk.java.net/jdk16u/pull/111