Remove deprecated TengoModifyMessage

This has become InMessage under [tengo]

matterbridge.toml.sample

@@ -1445,29 +1445,6 @@ MediaDownloadBlacklist=[".html$",".htm$"]
 #OPTIONAL (default false)
 IgnoreFailureOnStart=false
 
-
-#TengoModifyMessage allows you to specify the location of a tengo (https://github.com/d5/tengo/) script.
-#This script will receive every incoming message and can be used to modify the Username and the Text of that message.
-#The script will have the following global variables:
-#to modify: msgUsername and msgText
-#to read: msgChannel and msgAccount
-#
-#The script is reloaded on every message, so you can modify the script on the fly.
-#
-#Example script can be found in https://github.com/42wim/matterbridge/tree/master/gateway/bench.tengo
-#and https://github.com/42wim/matterbridge/tree/master/contrib/example.tengo
-#
-#The example below will check if the text contains blah and if so, it'll replace the text and the username of that message.
-#text := import("text")
-#if text.re_match("blah",msgText) {
-#    msgText="replaced by this"
-#    msgUsername="fakeuser"
-#}
-#More information about tengo on: https://github.com/d5/tengo/blob/master/docs/tutorial.md and
-#https://github.com/d5/tengo/blob/master/docs/stdlib.md
-#OPTIONAL (default empty)
-TengoModifyMessage="example.tengo"
-
 ###################################################################
 #Tengo configuration
 ###################################################################