[jdk8u-ri] RFR: 8303028: Update system property for Java SE specification maintenance version

[Justin Lu]

The system property: _java.specification.maintenance.version_ is updated to version 5 for the release.

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Commit messages:
 - Update Java SE Specification Maintenance version from 4 to 5

Changes: https://git.openjdk.org/jdk8u-ri/pull/12/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk8u-ri&pr=12&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8303028
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk8u-ri/pull/12.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-ri pull/12/head:pull/12

PR: https://git.openjdk.org/jdk8u-ri/pull/12