Bump actions/checkout from 2.3.4 to 2.4.0

Bumps [actions/checkout](https://github.com/actions/checkout) from 2.3.4 to 2.4.0.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@5a4ac90...ec3a7ce)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/draft.yml

@@ -27,7 +27,7 @@ jobs:
         key: ${{ runner.os }}-pip-
 
     - name: Clone
-      uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
+      uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579
 
     - name: Build specification
       run: |
@@ -36,7 +36,7 @@ jobs:
         make -f ../Makefile draft
 
     - name: Switch branch
-      uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
+      uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579
       with:
         ref: gh-pages
         clean: false

.github/workflows/pr.yml

@@ -9,7 +9,7 @@ jobs:
     name: Sanity checks before a PR merge
     runs-on: ubuntu-20.04
     steps:
-      - uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
+      - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579
         with:
           fetch-depth: 0 # we want all refs for the --is-ancestor check
 

.github/workflows/release.yml

@@ -27,7 +27,7 @@ jobs:
         key: ${{ runner.os }}-pip-
 
     - name: Clone main
-      uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
+      uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579
       with:
         fetch-depth: 0
 
@@ -62,7 +62,7 @@ jobs:
 
     - name: Switch branch
       if: steps.getver.outputs.spec_version != steps.prevver.outputs.prev_version
-      uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
+      uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579
       with:
         ref: gh-pages
         clean: false