fix: renamed shebang to make the examples python3 compliant

examples/caching_requestor.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 """Example program that shows how simple in-memory caching can be used.
 

examples/device_id_auth_trophies.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 """Example program that outputs a user's list of trophies.
 

examples/obtain_refresh_token.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 """Example program that demonstrates the flow for retrieving a refresh token.
 

examples/read_only_auth_trophies.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 """Example program that outputs a user's list of trophies.
 

examples/script_auth_friend_list.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 """script_auth_friend_list.py outputs the authenticated user's list of friends.