Use checkout action throughout

Author: tautschnig

.github/workflows/update-subtree.yml

@@ -18,13 +18,27 @@ jobs:
       uses: actions/checkout@v4
       with:
         fetch-depth: 0
+        path: verify-rust-std
 
     - name: Checkout Kani
       uses: actions/checkout@v4
       with:
         repository: model-checking/kani
         path: kani-tmp
 
+    - name: Checkout Rust
+      uses: actions/checkout@v4
+      with:
+        repository: rust-lang/rust
+        fetch-depth: 0
+        path: rust-tmp
+
+    - name: Checkout git-filter-repo
+      uses: actions/checkout@v4
+      with:
+        repository: newren/git-filter-repo
+        path: git-filter-repo
+
     - name: Fetch Kani toolchain version
       run: |
         cd kani-tmp
@@ -38,14 +52,9 @@ jobs:
         echo "TOOLCHAIN_DATE=${TOOLCHAIN_DATE}" >> $GITHUB_ENV
         echo "Kani toolchain hash: ${COMMIT_HASH}"
         echo "COMMIT_HASH=${COMMIT_HASH}" >> $GITHUB_ENV
-        cd ..
-        rm -r kani-tmp
 
     - name: Update subtree/library locally
       run: |
-        pushd ..
-        git clone [email protected]:newren/git-filter-repo
-        git clone [email protected]:rust-lang/rust rust-tmp
         cd rust-tmp
 
         # Ensure "upstream/master" branch contains the target commit
@@ -57,7 +66,8 @@ jobs:
         git checkout ${COMMIT_HASH}
         ../git-filter-repo/git-filter-repo --subdirectory-filter library --force
         git checkout -b subtree/library
-        popd
+
+        cd ../verify-rust-std
         git remote add rust-filtered ../rust-tmp/
         git fetch rust-filtered
         git checkout -b update-subtree/library rust-filtered/subtree/library
@@ -73,9 +83,11 @@ jobs:
         branch: update-subtree/library
         delete-branch: true
         base: subtree/library
+        path: verify-rust-std
 
     - name: Merge subtree/library changes
       run: |
+        cd verify-rust-std
         SYNC_BRANCH="sync-$TOOLCHAIN_DATE"
         git checkout -t -b ${SYNC_BRANCH} origin/main
         git submodule update --init
@@ -101,6 +113,7 @@ jobs:
           up to and including ${{ env.COMMIT_HASH }} of ${{ env.TOOLCHAIN_DATE }}
           into main. This is a clean merge, no conflicts were detected.
         delete-branch: true
+        path: verify-rust-std
 
     - name: Create Pull Request with conflicts
       if: ${{ env.MERGE_CONFLICTS == 'yes' }}
@@ -113,3 +126,4 @@ jobs:
           into main. `git merge` resulted in conflicts, which require manual resolution.
           Files were commited with merge conflict markers.
         delete-branch: true
+        path: verify-rust-std