Switch to .7z file extension

Signed-off-by: Daniel Weiße <dw@edgeless.systems>

.github/actions/artifact_download/action.yml

@@ -16,7 +16,7 @@ inputs:
 runs:
   using: "composite"
   steps:
-    - name: Install unzip
+    - name: Install 7zip
       uses: ./.github/actions/setup_bazel_nix
       with:
         nixTools: |
@@ -37,4 +37,4 @@ runs:
       shell: bash
       run: |
         mkdir -p ${{ inputs.path }}
-        7zz x -p'${{ inputs.encryptionSecret }}' -t7z -o"${{ inputs.path }}" ${{ steps.tempdir.outputs.directory }}/archive.zip
+        7zz x -p'${{ inputs.encryptionSecret }}' -t7z -o"${{ inputs.path }}" ${{ steps.tempdir.outputs.directory }}/archive.7z

.github/actions/artifact_upload/action.yml

@@ -22,7 +22,7 @@ inputs:
 runs:
   using: "composite"
   steps:
-    - name: Install zip
+    - name: Install 7zip
       uses: ./.github/actions/setup_bazel_nix
       with:
         nixTools: |
@@ -58,7 +58,7 @@ runs:
         for target in ${paths}
         do
           pushd "$(dirname "${target}")" || exit 1
-          7zz a -p'${{ inputs.encryptionSecret }}' -t7z -ms=on -mhe=on "${{ steps.tempdir.outputs.directory }}/archive.zip" "$(basename "${target}")"
+          7zz a -p'${{ inputs.encryptionSecret }}' -t7z -ms=on -mhe=on "${{ steps.tempdir.outputs.directory }}/archive.7z" "$(basename "${target}")"
           popd || exit 1
         done
 
@@ -66,7 +66,7 @@ runs:
       uses: actions/upload-artifact@5d5d22a31266ced268874388b861e4b58bb5c2f3 # v4.3.1
       with:
         name: ${{ inputs.name }}
-        path: ${{ steps.tempdir.outputs.directory }}/archive.zip
+        path: ${{ steps.tempdir.outputs.directory }}/archive.7z
         retention-days: ${{ inputs.retention-days }}
         if-no-files-found: ignore
         overwrite: ${{ inputs.overwrite }}