RFR: 8328811: Fix missing @Overrides in demos

[Ajit Ghaisas]

On Fri, 22 Mar 2024 15:54:42 GMT, Andy Goryachev <angorya at openjdk.org> wrote:

> Fixing missing @Overrides in demo apps.
> 
> This is still a trivial change since all the spots are identified by the IDE.

Looks good.

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Marked as reviewed by aghaisas (Reviewer).

PR Review: https://git.openjdk.org/jfx/pull/1426#pullrequestreview-1965855717