chore(ci): Give more control over where alt version jobs run

.github/workflows/ci.yml

@@ -56,7 +56,10 @@ jobs:
       run: cargo hack test --each-feature --workspace
   msrv:
     name: "Check MSRV"
-    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        os: ["ubuntu-latest"]
+    runs-on: ${{ matrix.os }}
     steps:
     - name: Checkout repository
       uses: actions/checkout@v5
@@ -70,7 +73,10 @@ jobs:
       run: cargo hack check --each-feature --locked --rust-version --ignore-private --workspace --all-targets --keep-going
   minimal-versions:
     name: Minimal versions
-    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        os: ["ubuntu-latest"]
+    runs-on: ${{ matrix.os }}
     steps:
     - name: Checkout repository
       uses: actions/checkout@v5

.github/workflows/rust-next.yml

@@ -46,7 +46,10 @@ jobs:
       run: cargo hack test --each-feature --workspace
   latest:
     name: "Check latest dependencies"
-    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        os: ["ubuntu-latest"]
+    runs-on: ${{ matrix.os }}
     env:
       CARGO_RESOLVER_INCOMPATIBLE_RUST_VERSIONS: allow
     steps: