contrib: deduplicate checksum calculation, use guix-check script

Author: kwvg

.github/workflows/guix-build.yml

@@ -63,14 +63,7 @@ jobs:
             echo "Guix build failed!"
             exit 1
           fi
-      - name: Compute SHA256 checksums for binaries
-        run: |
-          ( \
-          SRC_PATH_PREFIX=guix-build-$(git rev-parse --short=12 HEAD)/distsrc- && \
-          sha256sum ${SRC_PATH_PREFIX}*/src/dash{d,-cli,-tx,-wallet}{,.exe} && \
-          sha256sum ${SRC_PATH_PREFIX}*/src/qt/dash-qt{,.exe} && \
-          sha256sum ${SRC_PATH_PREFIX}*/src/test/test_dash{,.exe} \
-          ) | sort -k 2
-      - name: Compute SHA256 checksums for archives
+
+      - name: Compute SHA256 checksums
         run: |
-          find guix-build-"$(git rev-parse --short=12 HEAD)"/output -type f | grep -v SHA256 | xargs sha256sum | sort -k 2
+          ./contrib/containers/guix/scripts/guix-check ${{ github.workspace }}