Fix PATH being altered after installation even though choose not to (#787)

* Fix PATH being altered after installation even though choose not to

* Remove unuse updated list variable

get-poetry.py

@@ -598,6 +598,9 @@ class Installer:
         """
         Tries to update the $PATH automatically.
         """
+        if not self._modify_path:
+            return
+
         if WINDOWS:
             return self.add_to_windows_path()
 
@@ -606,7 +609,6 @@ class Installer:
 
         addition = "\n{}\n".format(export_string)
 
-        updated = []
         profiles = self.get_unix_profiles()
         for profile in profiles:
             if not os.path.exists(profile):
@@ -619,8 +621,6 @@ class Installer:
                 with open(profile, "a") as f:
                     f.write(u(addition))
 
-                updated.append(os.path.relpath(profile, HOME))
-
     def add_to_windows_path(self):
         try:
             old_path = self.get_windows_path_var()