[tserver] fix typo in generating name of tablet copy pool

Don't use std::string instance after calling std::move() on it:
even if it's in valid state, it's contents is unspecified, so
the result name for the thread pool isn't what it expected to be.

Change-Id: If7287fd1255e174482e81fdfc863f5f4140199d7
Reviewed-on: http://gerrit.cloudera.org:8080/21374
Tested-by: Alexey Serbin <alexey@apache.org>
Reviewed-by: Abhishek Chennaka <achennaka@cloudera.com>
1 file changed