Fix spell error in Russian translation, by enikulenkov.

Patch submitted as github pull request, see here:
https://github.com/enikulenkov/gnucash/commit/ceab7311fc6512349a73bfe927f7f0b53868d173
BP

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@22840 57a11ea4-9604-0410-9ed3-97b8803252fd