HPCC-10272 Fix banner dialog prompt

Change the name of the banner dialog prompt from "Server:" to "Banner Message:"

Signed-off by: Miguel Vazquez <miguel.vazquez@lexisnexis.com>
Merge branch 'HPCC-10272' into candidate-4.2.0

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>