RFR: 8303405: fix @returnss typo in ReflectionFactory

Wed Mar 1 00:30:55 UTC 2023

The following typo: `@returnss` was reported on line _482 of Reflection Factory.java_.

In addition to fixing that, I have replaced multiple instances of `@returns` with `@return` in the same file.

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Commit messages:
 - @return tag fix for methods

Changes: https://git.openjdk.org/jdk/pull/12794/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12794&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8303405
  Stats: 6 lines in 1 file changed: 0 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/12794.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12794/head:pull/12794

PR: https://git.openjdk.org/jdk/pull/12794