Update Wasmtime to 20.0.2

This commit updates the Wasmtime version used by Spin from 18.0.4 to
20.0.2. No motivation beyond keeping things up-to-date. This involved a
number of minor WASI refactorings such as moving some items around and
some refactorings around the `wasmtime-wasi-http` traits-and-types.
Notably the chained handler was switched from `anyhow::Result` to
`wasmtime_wasi_http::HttpResult` which helps make more explicit which
errors are traps and which are normal error codes.

Also update the MSRV of Spin to 1.75 as that's what Wasmtime requires

Signed-off-by: Alex Crichton <[email protected]>

Author: alexcrichton

.github/actions/spin-ci-dependencies/action.yml

@@ -8,7 +8,7 @@ inputs:
     type: bool
   rust-version:
     description: 'Rust version to setup'
-    default: '1.74'
+    default: '1.75'
     required: false
     type: string
 
@@ -72,7 +72,7 @@ inputs:
     required: false
     type: string
 
-  docker: 
+  docker:
     description: 'setup docker'
     required: false
     default: 'false'

.github/workflows/build.yml

@@ -21,7 +21,7 @@ concurrency:
 
 env:
   CARGO_TERM_COLOR: always
-  RUST_VERSION: 1.74
+  RUST_VERSION: 1.75
 
 jobs:
   dependency-review:

.github/workflows/release.yml

@@ -11,7 +11,7 @@ on:
 concurrency: ${{ github.workflow }}-${{ github.ref }}
 
 env:
-  RUST_VERSION: 1.74
+  RUST_VERSION: 1.75
 
 jobs:
   build-and-sign: