[lcio] set up run time paths (#18109)

* [lcio] set up run time paths

* [lcio] update runtime

* [lcio] flake8

var/spack/repos/builtin/packages/lcio/package.py

@@ -72,3 +72,7 @@ def url_for_version(self, version):
             print('Error - Wrong version format provided')
             return
         return url
+
+    def setup_run_environment(self, env):
+        env.set('LCIO', self.prefix)
+        env.prepend_path('PYTHONPATH', self.prefix.python)