📚 docs(README): Add missing import in code snippet.

Author: make-github-pseudonymous-again

README.md

@@ -5,6 +5,7 @@ SHA2 bytestring hashing for JavaScript.
 See [docs](https://string-hashing.github.io/sha2/index.html).
 
 ```js
+import {alloc} from '@array-like/alloc';
 import * as ascii from '@codec-bytes/ascii';
 import * as base16 from '@codec-bytes/base16';
 import {sha512} from '@string-hashing/sha2';