fix install script

Fix installer under ubuntu see also `https://npmjs.org/doc/scripts.html#EXAMPLES`

there is no `node` command only `nodejs` see `/usr/share/doc/nodejs/README.Debian`
```
nodejs command
--------------

The upstream name for the Node.js interpreter command is "node".
In Debian the interpreter command has been changed to "nodejs".

This was done to prevent a namespace collision: other commands use
the same name in their upstreams, such as ax25-node from the "node"
package.

Scripts calling Node.js as a shell command must be changed to instead
use the "nodejs" command.
```