workflows/release-binaries: Give attestation artifacts a unique name (#102041)

We need a different attestation for each supported architecture, so
there artifacts all need to have a different name.

The upload step is run on a Linux runner, so no matter which
architecture's binary is being uploaded the runner.os and runner.arch
variables would always be 'Linux' and 'X64' and so we can't use them for
naming the artifact.

Author: tstellar

.github/workflows/release-binaries.yml

@@ -442,7 +442,7 @@ jobs:
     - name: Upload Build Provenance
       uses: actions/upload-artifact@65462800fd760344b1a7b4382951275a0abb4808 #v4.3.3
       with:
-        name: ${{ runner.os }}-${{ runner.arch }}-release-binary-attestation
+        name: ${{ needs.prepare.outputs.release-binary-filename }}-attestation
         path: ${{ needs.prepare.outputs.release-binary-filename }}.jsonl
 
     - name: Upload Release