Releasing the write.lock part way through the retry budget raced with Lucene 3's
own lock bookkeeping: on Windows a competing Obtain left a handle on the file, so
Release and the temp directory cleanup both failed with a sharing violation. Hold
the lock for the whole budget instead and assert what actually matters, that a lock
conflict is retried and leaves the index files alone.
Co-authored-by: rmcrackan <rmcrackan@gmail.com>
