Update README.md

[akhilmanga]

I have added a community called Defenders Dao. It provides free resources to learn web3security(mostly) and blockchain development. And we create teams to participate in auditing contests. (I'm building this project).

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Summary by CodeRabbit

• New Feature: Added "Defenders Dao" to the list of communities in the Blockchain section. Users can now directly access the Discord invite link for this community from the README file.

[coderabbitai[bot]]

Walkthrough

This change introduces a new community, "Defenders Dao", to the Blockchain Communities list. The addition includes an invite link to their Discord server.

Changes

File	Summary
Blockchain/Communities/README.md	Added "Defenders Dao" community with a Discord invite link

🐇🎉

In the realm of code, changes small and grand,

A new community, in blockchain land.

Defenders Dao, they're called by name,

With a Discord link, they stake their claim.

So hop along, join the fun,

In the world of blockchain, there's work to be done! 🚀

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