RFR: 8369853: jpackage signing tests fail after JDK-8358723

[Alexey Semenyuk]

- Open "jdk.jpackage.internal.resources" package for jpackage tests instead of exporting it.
 - Fix a typo in test/jdk/tools/jpackage/helpers/jdk/jpackage/test/LauncherVerifier.java

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Commit messages:
 - 8369853: jpackage signing tests fail after JDK-8358723

Changes: https://git.openjdk.org/jdk/pull/27809/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=27809&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8369853
  Stats: 2 lines in 2 files changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/27809.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27809/head:pull/27809

PR: https://git.openjdk.org/jdk/pull/27809