RFR: 7504: Fix flightrecorder.writer.test project setup

[Marcus Hirt]

...so that it can be imported into Eclipse.

-------------

Commit messages:
 - Fixing redundant path
 - 7504: Fix flightrecorder.writer.test project setup

Changes: https://git.openjdk.java.net/jmc/pull/352/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jmc&pr=352&range=00
  Issue: https://bugs.openjdk.java.net/browse/JMC-7504
  Stats: 51 lines in 7 files changed: 41 ins; 1 del; 9 mod
  Patch: https://git.openjdk.java.net/jmc/pull/352.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/352/head:pull/352

PR: https://git.openjdk.java.net/jmc/pull/352