[jdk21u-dev] RFR: 8309841: Jarsigner should print a warning if an entry is removed

[Roman Marchenko]

This is backport of "8309841: Jarsigner should print a warning if an entry is removed"

Original patch does not apply cleanly to jdk21, some minor conflicts, and `_` was replaced with a variable in `test/jdk/sun/security/tools/jarsigner/RemovedFiles.java`.

We need this fix in jdk21 and below, down to jdk8, as all versions have this issue with `jarsigner`.

New tests successfully ran locally on Linux, x86_64.

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Commit messages:
 - Backport bdfb41f977258831e4b0ceaef5d016d095ab6e7f

Changes: https://git.openjdk.org/jdk21u-dev/pull/1440/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1440&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8309841
  Stats: 241 lines in 5 files changed: 240 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1440.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1440/head:pull/1440

PR: https://git.openjdk.org/jdk21u-dev/pull/1440