Update examples that require the run() method

[awaelchli]

What does this PR do?

Fixes #15088

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cc @Borda @rohitgr7 @Felonious-Spellfire

[tchaton]

LGTM ! But I personally find it confusing to run things which aren't doing anyting.

[awaelchli]

@tchaton what would be the alternative in your opinion? The run method needs to be there as per #14760. We could

def run():
    pass

but IMO the pattern should be to run the child components.