RFR: 8366002: Specification Update Needed: Beans.instantiate Serialized Object Loading Behavior

[Phil Race]

Some text describing the Beans.instantiate lookup process existed only on the method that used the now removed AppletInitializer.
Since there are two other Beans.instantiate methods, we need to move that text to the remaining methods.

Note that one of the methods is also deprecated for removal, so it seems prudent to add it to both so that when the next to be removed method is gone, this problem doesn't recur.

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

Commit messages:
 - 8366002

Changes: https://git.openjdk.org/jdk/pull/26905/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=26905&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8366002
  Stats: 32 lines in 1 file changed: 32 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/26905.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26905/head:pull/26905

PR: https://git.openjdk.org/jdk/pull/26905