RFR: Updated fix version

[Jesper Wilhelmsson]

Setting the fix version to 'N+1' results in having two backport records with the same fix version once the change is forwardported to mainline. This is a problem as JBS only show the oldest backport to each version in the list of backports.

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Commit messages:
 - Updated fix version

Changes: https://git.openjdk.java.net/guide/pull/76/files
 Webrev: https://webrevs.openjdk.java.net/?repo=guide&pr=76&range=00
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/guide/pull/76.diff
  Fetch: git fetch https://git.openjdk.java.net/guide pull/76/head:pull/76

PR: https://git.openjdk.java.net/guide/pull/76