README: rm bad sha256 hash example

Author: dcousens

README.md

@@ -109,7 +109,6 @@ Otherwise, pull requests are appreciated.
 Some examples interact (via HTTPS) with a 3rd Party Blockchain Provider (3PBP).
 
 - [Generate a random address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L22)
-- [Generate an address from a SHA256 hash](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L29)
 - [Import an address via WIF](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L40)
 - [Generate a 2-of-3 P2SH multisig address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L47)
 - [Generate a SegWit address](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/test/integration/addresses.js#L60)

test/integration/addresses.js

@@ -25,17 +25,6 @@ describe('bitcoinjs-lib (addresses)', function () {
     assert.strictEqual(address, '1F5VhMHukdnUES9kfXqzPzMeF1GPHKiF64')
   })
 
-  it('can generate an address from a SHA256 hash', function () {
-    const hash = bitcoin.crypto.sha256(Buffer.from('correct horse battery staple'))
-
-    const keyPair = bitcoin.ECPair.fromPrivateKey(hash)
-    const { address } = bitcoin.payments.p2pkh({ pubkey: keyPair.publicKey })
-
-    // Generating addresses from SHA256 hashes is not secure if the input to the hash function is predictable
-    // Do not use with predictable inputs
-    assert.strictEqual(address, '1C7zdTfnkzmr13HfA2vNm5SJYRK6nEKyq8')
-  })
-
   it('can import an address via WIF', function () {
     const keyPair = bitcoin.ECPair.fromWIF('Kxr9tQED9H44gCmp6HAdmemAzU3n84H3dGkuWTKvE23JgHMW8gct')
     const { address } = bitcoin.payments.p2pkh({ pubkey: keyPair.publicKey })