[jdk21u-dev] RFR: 8335530: Java file extension missing in AuthenticatorTest

[Goetz Lindenmaier]

I backport this for parity with 21.0.6-oracle.

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Commit messages:
 - Backport a537e87d2d2c6bff63f63bb436e3e919740221ce

Changes: https://git.openjdk.org/jdk21u-dev/pull/999/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=999&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8335530
  Stats: 120 lines in 2 files changed: 60 ins; 60 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/999.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/999/head:pull/999

PR: https://git.openjdk.org/jdk21u-dev/pull/999