fix: Ensure APP_PRIVATE_KEY is explicitly converted to string when provided as an argument

Author: BethanyJep

test.py

@@ -5,7 +5,7 @@
 # get private key from args
 
 if len(sys.argv) > 1:
-    APP_PRIVATE_KEY = sys.argv[1]
+    APP_PRIVATE_KEY = str(sys.argv[1])
 
 if APP_PRIVATE_KEY is None:
     print("Please provide the path to the private key file as an argument.")