[fix] fix retry command handling

* use eval "$cmd" to handle strings correctly
* add-apt-repo doesn't need dpkg lock so don't use retry for those lines

salt/common/tools/sbin/so-common

@@ -229,7 +229,7 @@ retry() {
 	while [[ $attempt -lt $maxAttempts ]]; do			
 		attempt=$((attempt+1))
 		echo "Executing command with retry support: $cmd"
-		output=$("$cmd")
+		output=$(eval "$cmd")
 		exitcode=$?
 		echo "Results: $output ($exitcode)"
 		if [ -n "$expectedOutput" ]; then