Fix links in not-so-smart-contracts

Author: elopez

not-so-smart-contracts/README.md

@@ -2,9 +2,9 @@
 
 This repository contains examples of common smart contract vulnerabilities, including code from real smart contracts. Use Not So Smart Contracts to learn about vulnerabilities, as a reference when performing security reviews, and as a benchmark for security and analysis tools:
 
-- [Algorand](./algorand/README.md)
-- [Cairo](./cairo/README.md)
-- [Cosmos](./cosmos/README.md)
-- [Solana](./solana/README.md)
-- [Substrate](./substrate/README.md)
-- [TON](./ton/README.md)
+- [Algorand](./algorand)
+- [Cairo](./cairo)
+- [Cosmos](./cosmos)
+- [Solana](./solana)
+- [Substrate](./substrate)
+- [TON](./ton)