RFR: 8328648: Remove applet usage from JFileChooser tests bug4150029

[Alisen Chung]

Removing applet usage from manual JFileChooser tests

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Commit messages:
 - remove extra dialog
 - init commit

Changes: https://git.openjdk.org/jdk/pull/18415/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18415&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8328648
  Stats: 116 lines in 2 files changed: 25 ins; 46 del; 45 mod
  Patch: https://git.openjdk.org/jdk/pull/18415.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18415/head:pull/18415

PR: https://git.openjdk.org/jdk/pull/18415