.github: possible fix of Bob's upload

Use same if: syntax for release/upload job as for build job.  Only thing
the upload job needs to ensure is that it does not try to upload built
artifacts from forks or from non-main builds.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

.github/workflows/build.yml

@@ -72,7 +72,7 @@ jobs:
         with:
           path: output/${{ steps.vars.outputs.tgz }}
   release:
-    if: github.repository == 'kernelkit/infix' && github.ref == 'refs/heads/main'
+    if: ${{github.repository == 'kernelkit/infix' && github.ref == 'refs/heads/main'}}
     name: Upload Latest Build
     needs: build
     runs-on: ubuntu-latest