RFR: 8320334: Reflow markdown in testing.md

[Iris Clark]

On Fri, 17 Nov 2023 16:39:54 GMT, Magnus Ihse Bursie <ihse at openjdk.org> wrote:

> In preparation for textual updates, the markdown in testing.md is reflowed so line lengths of 80 is respected, wherever possible. 
> 
> Note that is is correct  that the testing.html file is unchanged (and indeed a sign that only markdown line breaks have been modified).

Marked as reviewed by iris (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/16712#pullrequestreview-1737616656