Add test of error not getting silenced

tests/various/logger_cmd_error.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+
+trap 'echo "ERROR in logger_cmd_error.sh" >&2; exit 1' ERR
+
+(../../yosys -v 3 -C <<EOF
+yosys -import
+hierarchy -top nonexistent
+EOF
+) 2>&1 | grep -F "ERROR: Module \`nonexistent' not found!" > /dev/null