Add sgx build to CI

.github/workflows/test.yml

@@ -86,6 +86,28 @@ jobs:
         run: cargo build --target thumbv6m-none-eabi --color=always
         working-directory: ./ci/core-test
 
+  intel_sgx:
+    strategy:
+      matrix:
+        os: [ubuntu-latest]
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Install rust with fortanix sgx toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: nightly
+          target: x86_64-fortanix-unknown-sgx
+          override: true
+      - uses: Swatinem/rust-cache@v1
+
+      - name: Build sgx lib
+        run: cargo build --target x86_64-fortanix-unknown-sgx --color=always
+        working-directory: ./ci/core-test
+
   wasm:
     strategy:
       matrix: