Remove an extra space while clearing indexed stock items.

[nntoan]

Remove an extra space while clearing indexed stock items.
It should be

$this->itemsForReindex->clear();

instead of:

$this->itemsForReindex ->clear();

I know that the compiler doesn't complain about this at all, but shall we make it prettier? :)

[magento-cicd2]

All committers have signed the CLA.

[vrann]

@nntoan merged, thank you for the contribution!