Output SHA256 Checksum of Release Artifact

Author: harrryr

.github/workflows/release_build.yml

@@ -131,3 +131,14 @@ jobs:
              --draft \
              "v${{ github.event.inputs.version }}" \
              dist/aws_opentelemetry_distro-${{ github.event.inputs.version }}-py3-none-any.whl
+
+      - name: Get SHA256 checksum of wheel file
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          checksum=$(shasum -a 256 dist/aws_opentelemetry_distro-${{ github.event.inputs.version }}-py3-none-any.whl | awk '{ print $1 }')
+          echo "RELEASE_ARTIFACT_CHECKSUM_VALUES"
+          echo "aws_opentelemetry_distro-${{ github.event.inputs.version }}-py3-none-any.whl: $checksum"
+        
+          
+