[foreign-memaccess+abi] RFR: Clarify javadoc w.r.t. exceptions thrown by a memory access var handle (part two)

[Per Minborg]

On Mon, 21 Aug 2023 12:35:08 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

> This is a follow-up on https://git.openjdk.org/panama-foreign/pull/869 which fixes two issues:
> * the rectified javadoc still did not mention possibility of `WrongThreadException`
> * `MemoryLayout::sliceHandle` needs similar clarifications (albeit some exceptions can't occur there)
> 
> To make the javadoc a bit more streamlined, I've collected all the checks in bullet lists.

LGTM

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Marked as reviewed by pminborg (Committer).

PR Review: https://git.openjdk.org/panama-foreign/pull/872#pullrequestreview-1586920905