Fix
* Handle YaleXSBLEError while shutting down the lock connection ([154](https://github.com/bdraco/yalexs-ble/issues/154)) ([`787efa4`](https://github.com/bdraco/yalexs-ble/commit/787efa43ec95d3f6265b5d874af813fc3c937732))
* Add running guards to ensure cancel does not get suppressed ([153](https://github.com/bdraco/yalexs-ble/issues/153)) ([`f14fbee`](https://github.com/bdraco/yalexs-ble/commit/f14fbeee44682192c2f2bb2bedfc0ea8d641598d))