installed binary can't find shared library; built binary works fine

After building, running FaustLive from Build/bin works fine, but when running it from the install location (`/usr/local/bin/`) it can't find libHTTPDFaust.so.0:

```
FaustLive: error while loading shared libraries: libHTTPDFaust.so.0: cannot open shared object file: No such file or directory
```

This is on a linux machine running Pop!_OS 21.04.