ci: Prevent dependabot from messing with our MSRV

.github/workflows/ci.yml

@@ -16,16 +16,19 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/[email protected]
+      - uses: dtolnay/rust-toolchain@master # avoid the tag here to prevent dependabot from updating it
+        with:
+          toolchain: "1.70"
       - run: cargo check --all-targets --all-features
 
   fmt:
     name: cargo fmt
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@1.70
+      - uses: dtolnay/rust-toolchain@master # avoid the tag here to prevent dependabot from updating it
         with:
+          toolchain: "1.70"
           components: rustfmt
       - run: cargo fmt --all --check
 
@@ -34,16 +37,19 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/[email protected]
+      - uses: dtolnay/rust-toolchain@master # avoid the tag here to prevent dependabot from updating it
+        with:
+          toolchain: "1.70"
       - run: cargo test --all-targets --all-features
 
   clippy:
     name: cargo clippy
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@1.70
+      - uses: dtolnay/rust-toolchain@master # avoid the tag here to prevent dependabot from updating it
         with:
+          toolchain: "1.70"
           components: clippy
       - run: cargo clippy --all-targets --all-features -- -D warnings