Fixed issue 22348 - Specify forward referencing of MixinDeclaration

[RobertGrancsa]

Signed-off-by: Robert Grancsa robert.grancsa2002@gmail.com

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	22348	minor	Specify forward referencing of MixinDeclaration

[RazvanN7]

Please add a new commit that contains the "Fix Issue 22348 - [...]" in the commit meesage ("fixed" is not picked up by the bot).