use same install instruction within action-runner that also is used for the core action-runner

.gitea/workflows/tests.yaml

@@ -11,10 +11,33 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v4
-      - name: Install Neovim (AppImage)
+
+      - name: Install Neovim AppImage
+        shell: bash
         run: |
-          curl -L -o nvim.appimage https://github.com/neovim/neovim/releases/download/v0.11.4/nvim.appimage
-          chmod +x nvim.appimage
-          sudo mv nvim.appimage /usr/local/bin/nvim
-      - name: Run tests
+          set -euo pipefail
+          arch="$(uname -m)"
+          if [ "${arch}" = "aarch64" ]; then
+            appimage="nvim-linux-arm64.appimage"
+          else
+            appimage="nvim-linux-x86_64.appimage"
+          fi
+          url="https://github.com/neovim/neovim/releases/download/stable/${appimage}"
+          curl -L "${url}" -o "${appimage}"
+          chmod +x "${appimage}"
+          ./${appimage} --appimage-extract
+          sudo install -m 0755 ./squashfs-root/usr/bin/nvim /usr/local/bin/nvim
+
+      - name: Neovim Version
+        run: nvim --version
+
+      - name: Install plenary.nvim
+        shell: bash
+        run: |
+          set -euo pipefail
+          target_dir="${HOME}/.local/share/nvim/site/pack/vendor/start/plenary.nvim"
+          mkdir -p "$(dirname "${target_dir}")"
+          git clone --depth 1 https://github.com/nvim-lua/plenary.nvim "${target_dir}"
+
+      - name: Run Tests
         run: bash run_test.sh