fix(bindgen,format): enable wasm encoded to be used in the bindgen! macro

[mkatychev]

Use include_bytes en lieu of include_string to allow WASM encoded components to be passed into wasmtime::component::bindgen.

wit_parser::Resolve::push_path seems to already support wasm-encoded format (Added in bytecodealliance/wasm-tools#2415):

The input path can be one of:

• ...
• A wasm-encoded WIT package as a single file in either the text or binary format.

[mkatychev]

Couple of questions came up with this PR:

• should test cases be included in this PR or should that be handled upstream (this PR mainly exposes further the functionality of wit-parser)

• The wit-bindgen Config::expand method has already handled this case and is almost identical to the current bindgen::expand function (barring an extra rustfmt process in wasmtime), has there already been discussions about their similarity and possible reuse?