Apply suggestion from @Sayan- propagating conversion of test to if conditional

Co-authored-by: Sayan <[email protected]>

Author: matthewjmarangoni

shared/start-buildkit.sh

@@ -14,8 +14,7 @@ else
     return $?
 fi
 
-test "$(docker container inspect -f '{{.State.Running}}' buildkit 2> /dev/null)" = "true"
-if test $? -eq 0; then
+if [ "$(docker container inspect -f '{{.State.Running}}' buildkit 2> /dev/null)" = "true" ]; then
     echo "Container 'buildkit' is already running. Nothing to do."
 else
     echo "Starting 'buildkit' container ... "