RFR: 8323605: Java source launcher should not require `--source ...` to enable preview [v2]

[Christian Stein]

> Please review this PR targeting the source launcher that instead of throwing an error reading _"--enable-preview must be used with --source"_ adds the required compiler arguments on-the-fly.
> 
> The add arguments are `--release` and `feature`, with `feature` being the release feature number of the current Java runtime as acquired by `Runtime.version().feature()`.

Christian Stein has updated the pull request incrementally with one additional commit since the last revision:

  Update copyright dates
  
  [skip ci]

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Changes:
  - all: https://git.openjdk.org/jdk/pull/17731/files
  - new: https://git.openjdk.org/jdk/pull/17731/files/323e34b7..7883b861

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=17731&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=17731&range=00-01

  Stats: 3 lines in 3 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/17731.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17731/head:pull/17731

PR: https://git.openjdk.org/jdk/pull/17731