RFR: 8320342: Use PassFailJFrame for TruncatedPopupMenuTest.java

[Rajat Mahajan]

Modified the test to use PassFailJFrame and moved it from closed to open.
The test shows two windows, one for instructions and the other to perform testing on.
Tested locally and it works fine.

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Commit messages:
 - 8320342: Use PassFailJFrame for TruncatedPopupMenuTest.java

Changes: https://git.openjdk.org/jdk/pull/17641/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17641&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8320342
  Stats: 93 lines in 1 file changed: 93 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/17641.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17641/head:pull/17641

PR: https://git.openjdk.org/jdk/pull/17641