[jdk17u-dev] RFR: 8286475: Drop --enable-preview from instanceof pattern matching related tests

[Goetz Lindenmaier]

I backport this for parity with 17.0.10-oracle.

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Commit messages:
 - Backport 8c977050aa20a7e9a6d0d83d18dce25defcc7a46

Changes: https://git.openjdk.org/jdk17u-dev/pull/1785/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1785&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8286475
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1785.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1785/head:pull/1785

PR: https://git.openjdk.org/jdk17u-dev/pull/1785