RFR: 8373001: LauncherFromOptions.create() not properly handling FileAssociationNoExtensionsException.

[Alexey Semenyuk]

Throw an exception with a proper message instead of "throw new AssertionError()"

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Commit messages:
 - 8373001: LauncherFromOptions.create() not properly handling FileAssociationNoExtensionsException.

Changes: https://git.openjdk.org/jdk/pull/29233/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29233&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8373001
  Stats: 5 lines in 2 files changed: 2 ins; 1 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/29233.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29233/head:pull/29233

PR: https://git.openjdk.org/jdk/pull/29233