RFR: 8348410: Preview flag not checked during compilation resulting in runtime crash

[Archie Cobbs]

JEP 455 adds support for `switch`'ing on `long`, `float`, `double`, and `boolean`. Since this feature is still in preview, the `--enable-preview` flag is required. The compiler was properly checking that when the expressions had primitive type, but not when the expression a corresponding boxed type (i.e., `Long`, `Float`, `Double`, and `Boolean`). This resulted in `BootstrapMethodError` failures at runtime. This PR closes that loophole.

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Commit messages:
 - Fix typo in regression test @summary lines.
 - Check preview enabled for switch on boxed Booleam, Long, Float, or Double.

Changes: https://git.openjdk.org/jdk/pull/23303/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23303&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8348410
  Stats: 72 lines in 9 files changed: 69 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/23303.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23303/head:pull/23303

PR: https://git.openjdk.org/jdk/pull/23303