Add OSDC Discord Server link

[sidntrivedi]

Changes to be made

• OSDC has its Discord server at https://discord.gg/2sv322nY9v .
• It needs to be added here likewise as for other platforms - https://github.com/osdc/bots/blob/master/telegram-bot/main.go#L187-L188

Hi, If it is the first time that you contribute to the bot, follow these steps:

Write a comment in this issue thread to let other possible contributors know that you are working on this bug. For eg : Hey all, I would like to work on this issue., follow Contributing to the bot 🔥✨ and feel free to ask anything related to this issue ✌️.

[iLorah]

Hey! I would like to do this :)

[daemon1024]

Hi @iLorah , thanks for showing your interest to work on this 😁. Are you facing in difficulty in setting up the project or working on this? Feel free to drop your queries here ✌️