Clean build directories before CMake

Jenkinsfile

@@ -11,6 +11,7 @@ pipeline {
                 sh '''
                     cmake -S . -B build/linux -G Ninja -DCMAKE_BUILD_TYPE=Release
                     cmake --build build/linux
+                    archiveArtifacts artifacts: 'build/linux/test_app', fingerprint: true
                 '''
             }
         }
@@ -29,6 +30,7 @@ stage('Build Windows') {
               -DCMAKE_TOOLCHAIN_FILE=C:\\vcpkg\\scripts\\buildsystems\\vcpkg.cmake
 
             cmake --build build\\windows
+            archiveArtifacts artifacts: 'build/windows/test_app.exe', fingerprint: true
         '''
     }
 }