CI ARM debootstrap: do not check sigs

not really needed (the risk is low) and so remove to simplify

(--no-check-gpg is --no-check-sigs in newer debootstrap versions)

.github/workflows/arm-build.yml

@@ -20,12 +20,10 @@ jobs:
         include:
           - arch: armhf
             repo: http://mirrordirector.raspbian.org/raspbian/
-            keyring: /etc/apt/trusted.gpg
             qemu_bin_arch: arm
             deb_release: bullseye
           - arch: arm64
             repo: https://deb.debian.org/debian
-            keyring: /usr/share/keyrings/debian-archive-keyring.gpg
             qemu_bin_arch: aarch64
             deb_release: bullseye
 
@@ -66,12 +64,11 @@ jobs:
     - name: Debootstrap
       if: steps.cache-bootstrap.outputs.cache-hit != 'true'
       run: |
-        sudo apt install debootstrap debian-archive-keyring
+        sudo apt install debootstrap
         sudo rm -rf ~/chroot
         sudo mkdir -p ~/chroot/var/tmp
         sudo mv /var/tmp/*NDI* ~/chroot/var/tmp
-        wget http://archive.raspbian.org/raspbian.public.key -O - | sudo apt-key add -q
-        sudo debootstrap --keyring=${{ matrix.keyring }} --arch ${{ matrix.arch }} ${{ matrix.deb_release }} ~/chroot ${{ matrix.repo }}
+        sudo debootstrap --no-check-gpg --arch ${{ matrix.arch }} ${{ matrix.deb_release }} ~/chroot ${{ matrix.repo }}
         sudo cp -r $GITHUB_WORKSPACE/.github ~/chroot/
         sudo cp /usr/bin/qemu-${{ matrix.qemu_bin_arch }}-static ~/chroot/usr/bin/
         sudo -EH chroot ~/chroot /.github/scripts/Linux/arm/bootstrap.sh ${{ matrix.arch }}