DRTVWR-418: Fix line-break problem; also explicitly request bash.

build.sh

-#!/bin/sh
+#!/usr/bin/env bash
 
 # This is the custom build script for the viewer
 #
@@ -119,7 +119,7 @@ pre_build()
      -DGRID:STRING="\"$viewer_grid\"" \
      -DLL_TESTS:BOOL="$run_tests" \
      -DTEMPLATE_VERIFIER_OPTIONS:STRING="$template_verifier_options" $template_verifier_master_url \
-     "${SIGNING[@]}"
+     "${SIGNING[@]}" \
     || fatal "$variant configuration failed"
 
   end_section "Configure $variant"