Bump actions/checkout from 2 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 2 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2...v4)

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

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

.github/workflows/master.yml

@@ -17,7 +17,7 @@ jobs:
           go-version: 1.17.x
 
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - uses: actions/cache@v2
         with:

.github/workflows/pr.yml

@@ -11,7 +11,7 @@ jobs:
 
     steps:
       - name: Checkout Code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
@@ -36,7 +36,7 @@ jobs:
           go-version: 1.17.x
 
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - uses: actions/cache@v2
         with:
@@ -57,7 +57,7 @@ jobs:
 
     steps:
     - name: Checkout code
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
       with:
         ref: ${{ github.head_ref }}