RFR: 8332014: Fix `@since` tags in `jdk.jshell`

[Nizar Benalla]

Please review this small change that aims to make the `@since` in this module more accurate, these bugs were reported by the checker tool at #18934 

-field: jdk.jshell.Snippet.SubKind:RECORD_SUBKIND
This should have `@since` 17 as it was a Preview element in JDK 14-16

-method: java.util.List jdk.jshell.SourceCodeAnalysis.sourceToSnippets(java.lang.String)
-method: int jdk.jshell.tool.JavaShellToolBuilder.start(java.lang.String[])

both should have `@since` 10 instead of 9

Thanks

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Commit messages:
 - add `@since` tags

Changes: https://git.openjdk.org/jdk/pull/19166/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19166&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8332014
  Stats: 6 lines in 3 files changed: 5 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/19166.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19166/head:pull/19166

PR: https://git.openjdk.org/jdk/pull/19166