Update README.md

README.md

-please run this command on raspberry pi terminal <br>
-<b>curl -k https://gitlab.del.ac.id/lamboksinaga/node-red-custom/raw/master/install.sh | sh </b>
\ No newline at end of file
+<p>please run this command on raspberry pi terminal
+<pre>
+    <code>curl -k https://gitlab.del.ac.id/lamboksinaga/node-red-custom/raw/master/install.sh | sh</code>
+</pre>
\ No newline at end of file