ENG-6158: Build the elastic index during ElasticContext cloning.

There might be tuples in the new table by the time the elastic context is
cloned. We need to build the index so that the tuples can be included.
Add missing break
Merge pull request #1291 from VoltDB/truncate-table-fix

ENG-6158: Build the elastic index during ElasticContext cloning.
Merge branch 'master' into fourtwo-integration