Fix stale link

The link to https://docs.avax.network/learn/virtual-machines is stale

Signed-off-by: yacovm <yacovm@users.noreply.github.com>

README.md

@@ -7,7 +7,7 @@
 Each blockchain is an instance of a Virtual Machine (VM), much like an object in an object-oriented language is an instance of a class.
 That is, the VM defines the behavior of the blockchain.
 
-Subnet EVM is the [Virtual Machine (VM)](https://docs.avax.network/learn/avalanche/virtual-machines) that defines the Subnet Contract Chains. Subnet EVM is a simplified version of [Coreth VM (C-Chain)](https://github.com/ava-labs/coreth).
+Subnet EVM is the [Virtual Machine (VM)](https://docs.avax.network/learn/virtual-machines) that defines the Subnet Contract Chains. Subnet EVM is a simplified version of [Coreth VM (C-Chain)](https://github.com/ava-labs/coreth).
 
 This chain implements the Ethereum Virtual Machine and supports Solidity smart contracts as well as most other Ethereum client functionality.