Specify minimum rust version (#1127)

* Specify minimum rust version
* specify minimum rust version in GitHub CI

This improves the error reporting when the crate is
compiled with older versions of rustc.

Specifically, #1123 tracks instances of Ubuntu rustc
giving obscure errors when users attempt to compile
spotifyd

With this change, this error becomes

> error: package `spotifyd v0.3.3 (...)` cannot be built because it requires rustc 1.62 or newer, while the currently active rustc version is 1.61.0

which is much more helpful to users diagnosinig the issue.

Co-authored-by: Marli Frost <[email protected]>

Author: slondr

.github/workflows/ci.yml

@@ -55,6 +55,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
+        rust: [stable, 1.62.0]
         os: [macos-latest, ubuntu-latest]
         include:
           - os: macos-latest
@@ -66,7 +67,7 @@ jobs:
       - name: Installing Rust toolchain
         uses: actions-rs/toolchain@v1
         with:
-          toolchain: stable
+          toolchain: ${{ matrix.rust }}
           override: true
       - name: Installing macOS dependencies
         if: matrix.os == 'macos-latest'

Cargo.toml

@@ -6,6 +6,7 @@ description = "A Spotify daemon"
 repository = "https://github.com/Spotifyd/spotifyd"
 license = "GPL-3.0-only"
 version = "0.3.3"
+rust-version = "1.62"
 
 [dependencies]
 alsa = { version = "0.5", optional = true }