This is a request to backport a Hudson fix into Jenkins. This is a 2-line change done in Hudson Subversion plugin 2.3.3, SHA 37ca9c134702878e6bb824dde108d63c6df043d8

https://github.com/hudson-plugins/subversion-plugin/commit/37ca9c134702878e6bb824dde108d63c6df043d8

Rationale: subversion workspace often remains locked if previous svn update failed because of bad network connection, wiping the workspace is not useful for anything in this situation, rather the opposite.