Add riscv64 to Publish Binaries workflow

Author: eshattow

.github/workflows/publish_binaries.yml

@@ -33,6 +33,10 @@ jobs:
             os: macos-latest
           - target: x86_64-pc-windows-msvc
             os: windows-latest
+          - target: riscv64-unknown-linux-gnu
+            os: ubuntu-20.04
+          - target: riscv64-unknown-linux-musl
+            os: ubuntu-latest
           - target: aarch64-unknown-linux-gnu
             os: ubuntu-latest
     runs-on: ${{ matrix.os }}