fix rust language example

[voigt]

First of all, thank you for this great piece of software!

Following the rust language example lead to the following error:

cargo build --release --target wasm32-wasi
   Compiling worker v0.1.0 (/Users/c.voigt/tmp/wws/worker)
error[E0308]: mismatched types
  --> src/main.rs:7:1
   |
7  | #[worker]
   | ^^^^^^^^^
   | |
   | expected enum `Content`, found struct `String`
   | arguments to this function are incorrect
   |
   = note: expected struct `Response<Content>`
              found struct `Response<String>`
note: associated function defined here
  --> /Users/c.voigt/.cargo/git/checkouts/wasm-workers-server-167282fd3427d500/93e1165/kits/rust/src/io.rs:86:12
   |
86 |     pub fn from_response(response: Response<Content>, cache: HashMap<String, String>) -> Self {
   |            ^^^^^^^^^^^^^
   = note: this error originates in the attribute macro `worker` (in Nightly builds, run with -Z macro-backtrace for more info)

For more information about this error, try `rustc --explain E0308`.
error: could not compile `worker` due to previous error

I was able to run the example with the attached adjustments.

[vmwclabot]

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[vmwclabot]

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[Angelmmiguel]

Hey @voigt,

Thank you very much for your contribution 😄. I totally missed to fix that part of the example in the last update!

[vmwclabot]

@voigt, VMware has approved your signed contributor license agreement.

[Angelmmiguel]

The changes are already in production! Thank you 😄