ci(check-and-build-and-test): in the msrv job, only do the prerequisite step on Windows (the only place not doing it is a problem)

.github/workflows/check-and-build-and-test.yml

@@ -207,7 +207,8 @@ jobs:
           - runner: ubuntu-latest
             target: x86_64-unknown-linux-gnu
 
-          - runner: windows-latest
+          - prerequisite_step: rm ~/.cargo/bin/cargo.exe; rm ~/.cargo/bin/rust-analyzer.exe; rm ~/.cargo/bin/rustfmt.exe; rustup update
+            runner: windows-latest
             target: x86_64-pc-windows-msvc
     name: Verify MSRV of ${{ matrix.crate_directory }} for ${{ matrix.supporteds.target }} (on ${{ matrix.supporteds.runner }})
     runs-on: ${{ matrix.supporteds.runner }}
@@ -221,14 +222,9 @@ jobs:
           shared-key: ${{ matrix.supporteds.target }}-latest-variable
           cache-on-failure: "true"
 
-      - name: Delete existing cargo
-        run: rm ~/.cargo/bin/carg*
-      - name: Delete existing rust-analyzer
-        run: rm ~/.cargo/bin/rust-analyze*
-      - name: Delete existing rustfmt
-        run: rm ~/.cargo/bin/rustfm*
-
-      - run: rustup update
+      - name: Run prerequisite setup step
+        if: matrix.supporteds.prerequisite_step
+        run: ${{ matrix.supporteds.prerequisite_step }}
 
       - name: Install cargo-msrv
         uses: taiki-e/install-action@v2