Update wasm-opt to 0.116 (paritytech#1995)

Just keeping wasm-opt up to date.

I don't see anything in the [binaryen
changelog](https://github.com/WebAssembly/binaryen/blob/main/CHANGELOG.md)
that should affect substrate.

This release includes dwarf passes that were accidentally omitted from
previous versions of the wasm-opt crate. I suspect this will not affect
substrate as their omission hasn't been noticed until recently.

substrate/utils/wasm-builder/Cargo.toml

@@ -22,5 +22,5 @@ toml = "0.7.3"
 walkdir = "2.3.2"
 sp-maybe-compressed-blob = { path = "../../primitives/maybe-compressed-blob" }
 filetime = "0.2.16"
-wasm-opt = "0.114"
+wasm-opt = "0.116"
 parity-wasm = "0.45"