using message split ignores message options

[Markus-Rost]

When sending multiple messages using the message split option other options like allowedMentions are only added to the very last message send. This might result in uncontrolled role mentions or other issues.

var options = {
    split: { maxLength: 20 },
    allowedMentions: { parse: [] }
}

msg.channel.send( '<@12345>', options )
// '@mention' no notification

msg.channel.send( '<@12345>\n<@12345>\n<@12345>', options )
// '@mention' notification
// '@mention' notification
// '@mention' no notification

Further details:

• discord.js version: 12.2.0
• Node.js version: v12.13.0
• Operating system: Windows 10
• Priority this issue should have: medium, as it might result in uncontrolled role mentions.

• I have also tested the issue on latest master, commit hash:

[almostSouji]

should be fixed in the referenced PR.
Feel free to test it out and leave comments/reviews in the PR thread.

• npm i almostSouji/discord.js#ba90212331e8e5f6c9777b6cf6d3d0869f7d68e9 (one commit only)
• npm i almostSouji/discord.js#split-mentions (the branch the PR is from, including respective changes over time, if applicable)

reference: https://docs.npmjs.com/files/package.json#git-urls-as-dependencies