adds a ubuntu 24.04 matrix with gcc 14 for tests (#23673)

ref https://forum.nim-lang.org/t/11587

.github/workflows/ci_gcc14.yml

@@ -0,0 +1,76 @@
+name: GCC 14
+on:
+  pull_request:
+  push:
+    branches:
+      - 'devel'
+
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-24.04]
+        cpu: [amd64]
+    name: '${{ matrix.os }}'
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 60 # refs bug #18178
+    steps:
+      - name: 'Checkout'
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
+      - name: 'Install node.js 20.x'
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20.x'
+
+      - name: 'Install dependencies (Linux amd64)'
+        if: runner.os == 'Linux' && matrix.cpu == 'amd64'
+        run: |
+          sudo apt update -qq
+          sudo apt remove needrestart
+          DEBIAN_FRONTEND='noninteractive' \
+            sudo apt install --no-install-recommends -yq \
+              libcurl4-openssl-dev libgc-dev libsdl1.2-dev libsfml-dev \
+              valgrind libc6-dbg libblas-dev xorg-dev
+      - name: 'Install dependencies (Linux amd64 gcc 14)'
+        if: runner.os == 'Linux' && matrix.cpu == 'amd64'
+        run: |
+          sudo add-apt-repository universe
+          sudo apt update -qq
+          sudo apt install -y gcc-14 g++-14 libpcre3 liblapack-dev
+          sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-14 60 --slave /usr/bin/g++ g++ /usr/bin/g++-14
+      - name: 'Install dependencies (macOS)'
+        if: runner.os == 'macOS'
+        run: brew install boehmgc make sfml gtk+3
+      - name: 'Install dependencies (Windows)'
+        if: runner.os == 'Windows'
+        shell: bash
+        run: |
+          set -e
+          . ci/funs.sh
+          nimInternalInstallDepsWindows
+          echo_run echo "${{ github.workspace }}/dist/mingw64/bin" >> "${GITHUB_PATH}"
+
+      - name: 'Add build binaries to PATH'
+        shell: bash
+        run: echo "${{ github.workspace }}/bin" >> "${GITHUB_PATH}"
+
+      - name: 'NIM_TESTAMENT_DISABLE_SSL'
+        shell: bash
+        run: echo "NIM_TESTAMENT_DISABLE_SSL=1" >> $GITHUB_ENV
+
+      - name: 'System information'
+        shell: bash
+        run: . ci/funs.sh && nimCiSystemInfo
+
+      - name: 'Build csourcesAny'
+        shell: bash
+        run: . ci/funs.sh && nimBuildCsourcesIfNeeded CC=gcc ucpu='${{ matrix.cpu }}'
+
+      - name: 'koch, Run CI'
+        shell: bash
+        run: . ci/funs.sh && nimInternalBuildKochAndRunCI