Skip the 'download-dist' step for full integ-test

After the '[bot] update dist directory' commit, we run a full test suite.
This will now use the content from the 'dist' directory, rather than
regenerating this content in the test.

.github/actions/init-integ-test/action.yml

@@ -11,7 +11,7 @@ runs:
 
     # Downloads a 'dist' directory artifact that was uploaded in an earlier 'build-dist' step
     - name: Download dist
-      if: ${{ !env.ACT }}
+      if: ${{ env.SKIP_DIST != 'true' && !env.ACT }}
       uses: actions/download-artifact@v4
       with:
         name: dist