HPCC-10053 Display "busy" indicator on multi search

Fixes HPCC-10053

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>
Merge pull request #4967 from GordonSmith/HPCC-10053

HPCC-10053 Display "busy" indicator on multi search

Reviewed-By: Miguel Vazquez <miguel.vazquez@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>