refactor: streamlining of main function

Update utilizing walrus operators, only importing the sub-namespace we
need from os & sys.

autowl/__main__.py

@@ -1,16 +1,16 @@
-import os
 import discord
+from os import environ
+from sys import stderr
 
 
 # main runtime function
 def main():
-    try:
-        disToken = os.environ['DISCORD_TOKEN']  # grabs the discord token from the environment variable, if not there, exit
-    except:
-        print("ERROR: unable to find discord token in environment variables!")
+    if disToken := environ.get('DISCORD_TOKEN'):
+        print(f"Received discord token: {disToken}")
+        # Call into main action here, basically launch the bot via import to a lower module
+    else:
+        print("Unable to access DISCORD_TOKEN in environment!", file=stderr)
         exit(1)
 
-    print("hello world")
-
 
 main()