RFR: 8310667: Normalize comment blocks in newly-converted package-info.java files

[Kevin Rushforth]

This is a follow-up fix for [JDK-8180066](https://bugs.openjdk.org/browse/JDK-8180066). As mentioned in the description of PR #1159, we should normalize the javadoc comment blocks in the `package-info.java` files, which were converted from `package.html`.

In addition to being good cleanup, it also resolves a CI test failure that was introduced by [JDK-8180066](https://bugs.openjdk.org/browse/JDK-8180066), and is being tracked by [JDK-8310654](https://bugs.openjdk.org/browse/JDK-8310654).

The generated API docs are identical before and after this fix, excluding white-space changes. So the following show zero differences:


$ diff -w -r before/build/javadoc after/build/javadoc


Additionally, the following now passes, whereas it fails without this fix:


$ gradle :graphics:test

-------------

Commit messages:
 - 8310667: Normalize comment blocks in newly-converted package-info.java files

Changes: https://git.openjdk.org/jfx/pull/1160/files
 Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1160&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8310667
  Stats: 1368 lines in 39 files changed: 0 ins; 10 del; 1358 mod
  Patch: https://git.openjdk.org/jfx/pull/1160.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1160/head:pull/1160

PR: https://git.openjdk.org/jfx/pull/1160