Update `as-wasi` dependency in AssemblyScript client

The AssemblyScript implementation is currently pinned to v0.4.4 or `as-wasi`, and the new release that breaks building modules:

```
ERROR TS6054: File '~lib/as-wasi.ts' not found.

 import { Console } from "as-wasi";
                         ~~~~~~~~~
 in ~lib/@deislabs/wasi-experimental-http/index.ts(3,25)
```

We should bump `as-wasi` (and potentially AssemblyScript itself).