RFR: 8231436: Fix the applicability of a no- at Target annotation type

[Liam Miller-Cushon]

Please review this fix to add `ElementType.MODULE` to the default list of annotation targets, to allow annotations without an explicit `@Target` to be used on module declarations.

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Commit messages:
 - 8231436: Fix the applicability of a no- at Target annotation type

Changes: https://git.openjdk.java.net/jdk/pull/2303/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2303&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8231436
  Stats: 12 lines in 3 files changed: 10 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2303.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2303/head:pull/2303

PR: https://git.openjdk.java.net/jdk/pull/2303