ci: MSRV fixes

.github/workflows/rust.yml

@@ -108,9 +108,8 @@ jobs:
     - name: Checkout sources
       uses: actions/checkout@v3
 
-    # TODO: for now our latest release (0.19.1) requires nightly.
-    - name: Set nightly toolchain
-      run: cp .github/workflows/nightly_toolchain.toml rust-toolchain.toml
+    - name: Set MSRV toolchain
+      run: cp .github/workflows/msrv_toolchain.toml rust-toolchain.toml
 
     - name: Build
       run: cargo xtask test-latest-release
@@ -129,13 +128,13 @@ jobs:
         run: cargo xtask run --target x86_64 --ci
         timeout-minutes: 6
 
-  # Run the build with our current nightly MSRV (specified in
+  # Run the build with our current stable MSRV (specified in
   # ./msrv_toolchain.toml). This serves to check that we don't
   # accidentally start relying on a new feature without intending
   # to. Having a test for this makes it easier for us to be intentional
   # about making changes that require a newer version.
   build_msrv:
-    name: Check that the build works on our nightly MSRV
+    name: Check that the build works on our stable MSRV
     runs-on: ubuntu-latest
     steps:
     - name: Checkout sources

xtask/src/main.rs

@@ -207,9 +207,9 @@ fn run_host_tests(test_opt: &TestOpt) -> Result<()> {
 /// The `build` action also builds the template app, but due to the
 /// `patch.crates-io` of the top-level Cargo.toml the app is built using
 /// the current versions of the libraries in this repo. To give warning
-/// when the latest crates.io releases of the libraries are broken (due
-/// to changes in the nightly toolchain), this action copies the
-/// template to a temporary directory and builds it in isolation.
+/// when the latest crates.io releases of the libraries are broken, this
+/// action copies the template to a temporary directory and builds it in
+/// isolation.
 ///
 /// The build command is also checked against the contents of
 /// `building.md` to ensure that the doc correctly describes how to