Update to latest checkout GH action

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-22.04
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
       with:
         path: serv
 

.github/workflows/formal.yml

@@ -7,11 +7,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout riscv-formal
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: YosysHQ/riscv-formal
       - name: Checkout SERV
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: cores/serv/serv-src
       - uses: YosysHQ/setup-oss-cad-suite@v2

.github/workflows/lint.yml

@@ -11,7 +11,7 @@ jobs:
       VLNV : serv
     steps:
       - name: Checkout repo
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: serv
       - run: sudo apt install verilator

.github/workflows/openlane.yml

@@ -6,7 +6,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout subservient
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - name: Build with Openlane
         uses: librecores/ci-fusesoc-action@migrate-dockerized
         with:

.github/workflows/pages.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Checkout
-      uses: actions/checkout@v1
+      uses: actions/checkout@v4
     - name: Set up Python
       uses: actions/setup-python@v1
     - name: Install dependencies