Revert "refactor: remove explicit rust-toolchain install, rely on preinstalled version"

This reverts commit 320df78.

Author: nabil-Tounarti

.github/workflows/rust-build.yml

@@ -3,6 +3,10 @@ name: Build, Test and Publish Rust Package
 on:
   workflow_call:
     inputs:
+      rust-version:
+        description: 'Rust version to use'
+        default: 'stable'
+        type: string
       working-directory:
         description: 'The directory to run jobs from'
         default: '.'
@@ -30,8 +34,11 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
 
-      - name: Add clippy and rustfmt
-        run: rustup component add clippy rustfmt
+      - name: Install Rust toolchain
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: ${{ inputs.rust-version }}
+          components: clippy, rustfmt, cargo
 
       - name: Cache dependencies
         if: ${{ inputs.enable-cache }}

rust-build/README.md

@@ -22,6 +22,7 @@ jobs:
   build-and-test:
     uses: iExecBlockchainComputing/github-actions-workflows/.github/workflows/rust-build.yml@main
     with:
+      rust-version: 'stable'
       working-directory: './my-crate'
       enable-cache: true
       publish-crates-io: false
@@ -33,6 +34,7 @@ jobs:
 
 | Name                | Description                                               | Default  | Required |
 | ------------------- | --------------------------------------------------------- | -------- | -------- |
+| `rust-version`      | Rust version to use                                       | `stable` | No       |
 | `working-directory` | The directory to run jobs from                            | `.`      | No       |
 | `enable-cache`      | Enable caching of dependencies                            | `true`   | No       |
 | `publish-crates-io` | Publish the package to crates.io (only if build succeeds) | `false`  | No       |