[BUG] v3.3.7 of Click Analytics is throwing a `ReferenceError: Cannot access xxx before initialization`

[MSNev]

As part of the changes in v3.3.7, this is causing a ReferenceError exception to be thrown when run in strict mode.

This is due to the following code

        let unloadHandler: IUnloadHook = onConfigChange(_config, () => {
            _clickCaptureElements =  arrMap(_config.trackElementTypes.toUpperCase().split(","), tag => strTrim(tag));
        });
        let _clickCaptureElements: string[];

The onConfigChange is run synchronously and attempts to "set" the local variable which does not yet exist.

The fix is simply to define the variable before the onConfigChange call.