RichTextComposer::setEnableActions: use RichTextComposerActions::setActionsEnabled

The old code doesn't set the flag richTextEnabled, which results in
some actions being enabled and some being disabled due to checks in
slotUpdateMiscActions.
1 job for master in 5 minutes and 39 seconds (queued for 2 seconds)
Status Job ID Name Coverage
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passed #48339
linux kf5-qt5 qt5.12

00:05:39

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