Posting a discord message URL breaks bot

I just...

guh.

Output from console;
```bash
/usr/src/app/bot.js:51
for (let i = 0; i < lastMessage.content.length; i++) {
^

TypeError: Cannot read property 'content' of undefined
at /usr/src/app/bot.js:51:39
at runMicrotasks ()
at processTicksAndRejections (node:internal/process/task_queues:96:5)
Auth token from environment
Bot config from environment
Signed in, Ready to rock and roll
/usr/src/app/bot.js:51
for (let i = 0; i < lastMessage.content.length; i++) {
^
```