deps: update actions/checkout action to v4 (#6401)

Author: renovate-bot

.github/workflows/ci.yaml

@@ -27,7 +27,7 @@ jobs:
       matrix:
         java: [11, 17, 21]
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-java@v3
       with:
         distribution: temurin
@@ -41,7 +41,7 @@ jobs:
     name: "units (8)"
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: actions/setup-java@v3
         with:
           java-version: 8
@@ -63,7 +63,7 @@ jobs:
     steps:
     - name: Support longpaths
       run: git config --system core.longpaths true
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-java@v3
       with:
         distribution: temurin
@@ -78,7 +78,7 @@ jobs:
       matrix:
         java: [17]
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-java@v3
       with:
         distribution: temurin
@@ -88,7 +88,7 @@ jobs:
   javadoc:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-java@v3
       with:
         distribution: temurin
@@ -100,7 +100,7 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-java@v3
       with:
         distribution: temurin
@@ -112,7 +112,7 @@ jobs:
   clirr:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-java@v3
       with:
         distribution: temurin