RFR: 8330701: Fix Eclipse project in tests/manual/text

[Andy Goryachev]

Came out of the work on [JDK-8319555](https://bugs.openjdk.org/browse/JDK-8319555): [TestBug] Utility for creating instruction window for manual tests.

This project generates errors if opened in Eclipse. Yes, I can close the project each time, but I would rather fix the setup. This fix is extracted from
https://github.com/openjdk/jfx/pull/1413

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Commit messages:
 - 8330701: Fix Eclipse project in tests/manual/text

Changes: https://git.openjdk.org/jfx/pull/1443/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1443&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8330701
  Stats: 5 lines in 1 file changed: 5 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jfx/pull/1443.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1443/head:pull/1443

PR: https://git.openjdk.org/jfx/pull/1443