Add CMake 3.25 upgrade step to CI workflows and revert CMakeLists.txt

Co-authored-by: hsluoyz <3787410+hsluoyz@users.noreply.github.com>
diff --git a/.github/workflows/benchmark.yml b/.github/workflows/benchmark.yml
index 6f21356..367b35d 100644
--- a/.github/workflows/benchmark.yml
+++ b/.github/workflows/benchmark.yml
@@ -28,6 +28,10 @@
       - name: Checkout
         id: checkout
         uses: actions/checkout@v4
+      - name: Setup CMake
+        uses: jwlawson/actions-setup-cmake@v2
+        with:
+          cmake-version: '3.25.x'
       - name: Configuring CMake files
         id: building-files
         run: |
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 112813d..35c0fde 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -28,6 +28,10 @@
       - name: Checkout
         id: checkout
         uses: actions/checkout@v4
+      - name: Setup CMake
+        uses: jwlawson/actions-setup-cmake@v2
+        with:
+          cmake-version: '3.25.x'
       - name: Configuring CMake files
         id: building-files
         run: |
@@ -53,6 +57,10 @@
       - name: Checkout
         id: checkout
         uses: actions/checkout@v4
+      - name: Setup CMake
+        uses: jwlawson/actions-setup-cmake@v2
+        with:
+          cmake-version: '3.25.x'
       - name: Configuring CMake files
         id: building-files
         run: |
@@ -77,6 +85,10 @@
       - name: Checkout
         id: checkout
         uses: actions/checkout@v4
+      - name: Setup CMake
+        uses: jwlawson/actions-setup-cmake@v2
+        with:
+          cmake-version: '3.25.x'
       - name: Configuring CMake files
         id: building-files
         run: |
diff --git a/.github/workflows/memcheck.yml b/.github/workflows/memcheck.yml
index 4f2d442..08dc207 100644
--- a/.github/workflows/memcheck.yml
+++ b/.github/workflows/memcheck.yml
@@ -28,6 +28,10 @@
       - name: Checkout
         id: checkout
         uses: actions/checkout@v4
+      - name: Setup CMake
+        uses: jwlawson/actions-setup-cmake@v2
+        with:
+          cmake-version: '3.25.x'
       - name: Install requirement
         id: install-requirements
         run: |
diff --git a/CMakeLists.txt b/CMakeLists.txt
index e966e4a..cf6415b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -12,7 +12,7 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 
-cmake_minimum_required(VERSION 3.21)
+cmake_minimum_required(VERSION 3.19)
 
 set(CMAKE_WARN_DEPRECATED ON)
 set(PY_CASBIN_VERSION 1.1)