[Fix] Codebook directive now creates a file if it does not exist

Author: DerAndereJohannes

docs/directives/csv_codebook_directive.py

@@ -36,7 +36,7 @@ def run(self):
             doc_sensor = abrv_to_sensor[maybe_sensor[0]]
 
         # Open the CSV file and append the content
-        with open(csv_file_path, 'a', newline='', encoding='utf-8') as csvfile:
+        with open(csv_file_path, 'a+', newline='', encoding='utf-8') as csvfile:
             writer = csv.writer(csvfile)
 
             # Write header if file is newly created or empty