Run benchmarks on CI

These values are only for reference, and shouldn't be taken too
seriously. If at any time there is some serious performance regression
we should be able to see it though.

Signed-off-by: Rodrigo Tobar <rtobar@icrar.org>

.github/workflows/benchmark.yml

@@ -0,0 +1,31 @@
+name: Run benchmarking tool
+
+# Build on every branch push, tag push, and pull request change:
+on:
+  push:
+  pull_request:
+
+jobs:
+  run_benchmark:
+    name: Benchmark os=${{ matrix.os }}/sw_mode=${{ matrix.sw_mode}}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-22.04, windows-2019, macos-12]
+        sw_mode: [force, auto]
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        name: Install Python
+        with:
+          python-version: '3.7'
+
+      - name: Install crc32c
+        run: python setup.py develop
+
+      - name: Benchmark with 1 [GB] 10 times
+        env:
+          CRC32C_SW_MODE: ${{ matrix.sw_mode }}
+        run: python -m crc32c.benchmark -i 10 -s 1000000