ci: upgrade checkout action to v5 (#6)

- replace actions/checkout@v4 with @v5 across repository workflows\n- remove Node20 deprecation warning source in CI annotations

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: LessUp

.github/workflows/benchmark.yml

@@ -19,7 +19,7 @@ jobs:
       CXX: g++-12
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Install dependencies
         run: |

.github/workflows/ci-docs.yml

@@ -21,7 +21,7 @@ jobs:
       VITEPRESS_BASE: /cpp-high-performance-guide/
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Set up Node.js
         uses: actions/setup-node@v4

.github/workflows/ci.yml

@@ -19,7 +19,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Install clang-format
         run: |
@@ -37,7 +37,7 @@ jobs:
       CXX: g++-12
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Cache CMake dependencies
         uses: actions/cache@v4
@@ -72,7 +72,7 @@ jobs:
       CXX: clang++
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Cache CMake dependencies
         uses: actions/cache@v4
@@ -104,7 +104,7 @@ jobs:
     runs-on: macos-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Cache CMake dependencies
         uses: actions/cache@v4

.github/workflows/pages.yml

@@ -27,7 +27,7 @@ jobs:
       url: ${{ steps.deploy.outputs.page_url }}
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Set up Node.js
         uses: actions/setup-node@v4

.github/workflows/sanitizers.yml

@@ -21,7 +21,7 @@ jobs:
       CXX: g++-12
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Install dependencies
         run: |
@@ -45,7 +45,7 @@ jobs:
       CXX: clang++
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Install dependencies
         run: |
@@ -69,7 +69,7 @@ jobs:
       CXX: g++-12
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Install dependencies
         run: |