build: slight renaming of provenance output to meet best practice (#241)

Adding `-provenance` suffix to make the provenance artifacts clearer to
consumers. Additionally, renaming `macos-` prefix to `mac-` to match the
prefix of the mac build artifacts, per guidance from
https://slsa.dev/spec/v1.0/distributing-provenance#relationship-between-artifacts-and-attestations

Author: rsoberano-ld

.github/workflows/manual-sdk-release-artifacts.yml

@@ -69,4 +69,4 @@ jobs:
       base64-subjects: "${{ needs.release-sdk.outputs[format('hashes-{0}', matrix.os)] }}"
       upload-assets: true 
       upload-tag-name: ${{ inputs.tag }}
-      provenance-name: ${{ format('{0}-multiple.intoto.jsonl', matrix.os) }}
+      provenance-name: ${{ format('{0}-multiple-provenance.intoto.jsonl', matrix.os) }}

.github/workflows/release-please.yml

@@ -57,4 +57,4 @@ jobs:
       base64-subjects: "${{ needs.release-client.outputs[format('hashes-{0}', matrix.os)] }}"
       upload-assets: true 
       upload-tag-name: ${{ needs.release-please.outputs.package-client-tag }}
-      provenance-name: ${{ format('{0}-multiple.intoto.jsonl', matrix.os) }}
+      provenance-name: ${{ format('{0}-multiple-provenance.intoto.jsonl', matrix.os) }}