[jdk11u-dev] RFR: 8215015: [TESTBUG] remove unneeded -Xfuture option from tests

[Goetz Lindenmaier]

I backport this for parity with 11.0.20-oracle.

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Commit messages:
 - Backport 5a23b59ca07a78fa8a0214122c08857ab9fd984c

Changes: https://git.openjdk.org/jdk11u-dev/pull/1843/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1843&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8215015
  Stats: 6 lines in 3 files changed: 0 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1843.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/1843/head:pull/1843

PR: https://git.openjdk.org/jdk11u-dev/pull/1843