ci: style check for MSRV and stable

Author: phip1611

.github/workflows/rust.yml

@@ -15,9 +15,9 @@ jobs:
     strategy:
       matrix:
         rust:
+          - 1.52.1 # MSRV
           - stable
           - nightly
-          - 1.52.1 # MSVR
     steps:
       - uses: actions/checkout@v2
       # Important preparation step: override the latest default Rust version in GitHub CI
@@ -39,9 +39,9 @@ jobs:
     strategy:
       matrix:
         rust:
+          - 1.52.1 # MSRV
           - stable
           - nightly
-          - 1.52.1 # MSVR
     steps:
       - uses: actions/checkout@v2
       # Important preparation step: override the latest default Rust version in GitHub CI
@@ -58,13 +58,12 @@ jobs:
       - name: Build (no_std)
         run: cargo build --target thumbv7em-none-eabihf
 
-
-  # As discussed, these tasks are optional for PRs.
   style_checks:
     runs-on: ubuntu-latest
     strategy:
       matrix:
         rust:
+          - 1.52.1 # MSRV
           - stable
     steps:
       - uses: actions/checkout@v2