Testing - Update CI workflow to build and test on Ubuntu with GCC (#1028)

- Replaced macOS Clang (No PCH) job with Ubuntu GCC (No PCH) job in the workflow dependency list
- Updated the build job to use `ubuntu-24.04` runner with GCC compiler instead of `macos-15` with Clang
- Updated the test job to run on Ubuntu with GCC instead of macOS with Clang

.github/actions/build-occt/action.yml

@@ -31,6 +31,10 @@ inputs:
     description: 'CMake build type (Release, Debug, etc)'
     required: false
     default: 'Release'
+  build-parallel-jobs:
+    description: 'Number of parallel build jobs (empty for auto)'
+    required: false
+    default: ''
   github-token:
     description: 'GitHub token for vcpkg NuGet package access'
     required: true
@@ -75,7 +79,11 @@ runs:
       if: ${{ inputs.platform == 'linux' }}
       run: |
         cd build
-        cmake --build . --target install --config Release -- -j
+        if [ -n "${{ inputs.build-parallel-jobs }}" ]; then
+          cmake --build . --target install --config Release -- -j${{ inputs.build-parallel-jobs }}
+        else
+          cmake --build . --target install --config Release -- -j
+        fi
       shell: bash
 
     - name: Upload install directory

.github/workflows/build-and-test-multiplatform.yml

@@ -63,7 +63,7 @@ jobs:
       - run-gtest-windows-x64
       - run-gtest-macos-x64
       - run-gtest-linux-clang-x64
-      - run-gtest-macos-clang-no-pch
+      - run-gtest-linux-gcc-no-pch
 
     steps:
     - name: Checkout repository
@@ -120,10 +120,10 @@ jobs:
         artifact-name: install-linux-clang-x64
         github-token: ${{ secrets.GITHUB_TOKEN }}
 
-  prepare-and-build-macos-clang-no-pch:
-    name: Prepare and Build on macOS with Clang (No PCH)
-    needs: prepare-and-build-macos-x64
-    runs-on: macos-15
+  prepare-and-build-linux-gcc-no-pch:
+    name: Prepare and Build on Ubuntu with GCC (No PCH)
+    needs: prepare-and-build-linux-clang-x64
+    runs-on: ubuntu-24.04
 
     steps:
     - name: Checkout repository
@@ -132,13 +132,14 @@ jobs:
     - name: Build OCCT
       uses: ./.github/actions/build-occt
       with:
-        platform: macos
-        compiler: clang
-        artifact-name: install-macos-clang-no-pch
+        platform: linux
+        compiler: gcc
+        artifact-name: install-linux-gcc-no-pch
         build-use-pch: 'false'
         build-opt-profile: 'Default'
-        additional-cmake-flags: '-D CMAKE_CXX_FLAGS="-Werror -Wall -Wextra -Wno-error=cast-function-type-mismatch -Wno-error=deprecated-declarations" -D CMAKE_C_FLAGS="-Werror -Wall -Wextra -Wno-error=cast-function-type-mismatch -Wno-error=deprecated-declarations"'
+        additional-cmake-flags: '-D CMAKE_CXX_FLAGS="-Werror -Wall -Wextra -Wno-error=cast-function-type -Wno-error=deprecated-declarations" -D CMAKE_C_FLAGS="-Werror -Wall -Wextra -Wno-error=cast-function-type -Wno-error=deprecated-declarations"'
         cmake-build-type: 'Debug'
+        build-parallel-jobs: '4'
         github-token: ${{ secrets.GITHUB_TOKEN }}
 
   test-windows-x64:
@@ -300,10 +301,10 @@ jobs:
         install-artifact-name: install-linux-clang-x64
         artifact-suffix: x64
 
-  run-gtest-macos-clang-no-pch:
-    name: Run GTest on macOS with Clang (No PCH, Debug)
-    needs: prepare-and-build-macos-clang-no-pch
-    runs-on: macos-15
+  run-gtest-linux-gcc-no-pch:
+    name: Run GTest on Ubuntu with GCC (No PCH, Debug)
+    needs: prepare-and-build-linux-gcc-no-pch
+    runs-on: ubuntu-24.04
 
     steps:
     - name: Checkout repository
@@ -312,9 +313,9 @@ jobs:
     - name: Run GTests
       uses: ./.github/actions/run-gtest
       with:
-        platform: macos
-        compiler: clang
-        install-artifact-name: install-macos-clang-no-pch
+        platform: linux
+        compiler: gcc
+        install-artifact-name: install-linux-gcc-no-pch
         artifact-suffix: no-pch
 
   test-summary: