Fix multiple cores 1.8 (#3477)

First step into elastic scaling: Having a para be on multiple cores,
will not get it more throughput yet, but it will no longer brick it.

This is a backport PR, as this would benefit the Coretime launch on
Kusama.

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Signed-off-by: Andrei Sandu <[email protected]>
Signed-off-by: alindima <[email protected]>
Co-authored-by: Andrei Sandu <[email protected]>
Co-authored-by: alindima <[email protected]>
Co-authored-by: eskimor <[email protected]>