tools: silence version comparison in get_build_info()

The get_build_info() function uses nvrGreaterOrEqual() to determine how
to parse the output from composer-cli.  The function prints the result
of the comparison but is often used in a loop when waiting for a compose
to finish, which makes CI logs very annoying.

Silence the version comparison output when called form get_build_info().

test/cases/shared_lib.sh

@@ -26,7 +26,7 @@ function get_build_info() {
     local fname="$2"
     if rpm -q --quiet weldr-client; then
         key=".body${key}"
-        if nvrGreaterOrEqual "weldr-client" "35.6"; then
+        if nvrGreaterOrEqual "weldr-client" "35.6" 2> /dev/null; then
             key=".[0]${key}"
         fi
     fi