[CI] Set up Release build type for all platforms

Author: KvanTTT

.github/workflows/build.yml

@@ -34,7 +34,7 @@ jobs:
     - name: Configure CMake
       working-directory: cpp
       run: |
-        cmake . -DUSE_BACKEND=OPENCL -DNO_GIT_REVISION=1
+        cmake . -DUSE_BACKEND=OPENCL -DNO_GIT_REVISION=1 -DCMAKE_BUILD_TYPE=Release
 
     - name: Build
       working-directory: cpp
@@ -78,7 +78,7 @@ jobs:
       - name: Configure CMake
         working-directory: cpp
         run: |
-          cmake . -G Ninja -DUSE_BACKEND=OPENCL -DNO_GIT_REVISION=1
+          cmake . -G Ninja -DUSE_BACKEND=OPENCL -DNO_GIT_REVISION=1 -DCMAKE_BUILD_TYPE=Release
       - name: Build
         working-directory: cpp
         run: |