fix: #34 remove unused line in example

Author: polarmutex

example.beancount

@@ -10,7 +10,6 @@ option "operating_currency" "USD"
 2010-01-01 custom "fava-extension" "fava_envelope" "{}"
 2010-01-01 custom "envelope" "start date" "2015-01"
 2010-01-01 custom "envelope" "budget account" "Assets:US:BofA:Checking"
-2015-01-01 custom "envelope" "repeating" "Expenses:Financial:Fees" 4
 2015-01-01 custom "envelope" "allocate" "Expenses:Health:Dental:Insurance" 5.80
 2017-06-01 custom "envelope" "allocate" "Expenses:Financial:Fees" 0