RFR: 8304840: Dangling `CharacterCodingException` in a few javadoc descriptions

[Iris Clark]

On Tue, 28 Mar 2023 18:25:21 GMT, Naoto Sato <naoto at openjdk.org> wrote:

> Fixing a documentation bug for `CharacterCodingException` without any description to it as attached. A corresponding CSR is also drafted.
> 
> ![Screenshot 2023-03-28 at 11 19 00 AM](https://user-images.githubusercontent.com/3122603/228332508-74606c64-bce1-4135-a4cf-b0c76b902676.png)

Associated CSR also Reviewed.

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Marked as reviewed by iris (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/13214#pullrequestreview-1361791244