add an empty cell before header rows

test/data/check-snmp-agent-configs.py

@@ -14,6 +14,8 @@ def write_row_csv(columns, header=False):
 
 def write_row_md(columns, header=False):
     delimiter = '||' if header else '|'
+    if header:
+      columns = [' '] + columns
     print(delimiter + delimiter.join(columns) + delimiter)