update default php 7.3

Author: usmannasir

plogical/upgrade.py

@@ -2151,7 +2151,7 @@ def upgrade():
         except:
             pass
 
-        command = 'cp /usr/local/lsws/lsphp72/bin/lsphp %s' % (phpPath)
+        command = 'cp /usr/local/lsws/lsphp73/bin/lsphp %s' % (phpPath)
         Upgrade.executioner(command, 0)