Minor: Added exist_ok to project directory os.makedirs in main

Author: alongd

arc/main.py

@@ -281,8 +281,7 @@ def __init__(self,
         self.verbose = verbose
         self.project_directory = project_directory if project_directory is not None \
             else os.path.join(ARC_PATH, 'Projects', self.project)
-        if not os.path.exists(self.project_directory):
-            os.makedirs(self.project_directory)
+        os.makedirs(self.project_directory, exist_ok=True)
         self.output = output
         self.output_multi_spc = output_multi_spc
         self.standardize_output_paths()  # depends on self.project_directory