RFR: 8303473: Add implied {@code} in java.lang.invoke.MethodHandles

[Pavel Rappo]

Please review this trivial fix for _comments_. While some affected comments aren't doc comments and none of the affected comments partake in the API Documentation, it seems reasonable to be consistent.

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Commit messages:
 - Initial commit

Changes: https://git.openjdk.org/jdk/pull/12811/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12811&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8303473
  Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/12811.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12811/head:pull/12811

PR: https://git.openjdk.org/jdk/pull/12811