Update version 0.9.0.dev3 -> 0.9.0.dev4
Update version 0.9.0.dev3 -> 0.9.0.dev4

Fixes
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* Fix deserialization of variables that are nested tuples
* Include `shapeablebqm.pyx.src` in the `manifest.ini`
dwavesystems/dimod,dwavesystems/dimod