GH-6: Add test CI: i386 (#106)

Fix #6

This part: https://github.com/apache/arrow/blob/58415d1fac50cb829b3dcf08526033d6db8c30db/.github/workflows/go.yml#L165-L190

.github/workflows/test.yml

@@ -146,3 +146,26 @@ jobs:
       - name: Test
         shell: bash
         run: ci/scripts/test.sh $(pwd)
+  build_test_386:
+    name: Cross-build and test for 386
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - name: Checkout
+        uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
+        with:
+          submodules: recursive
+      - name: Get required Go version
+        run: |
+          (. .env && echo "GO_VERSION=${GO}") >> $GITHUB_ENV
+      - name: Setup Go
+        uses: actions/setup-go@0a12ed9d6a96ab950c8f026ed9f722fe0da7ef32 # v5.0.2
+        with:
+          go-version: "${{ env.GO_VERSION }}"
+          cache: true
+          cache-dependency-path: go.sum
+      - name: Build
+        run: GOARCH=386 go build ./...
+      - name: Test
+        # WIP refactor, only tests in the specified dirs have been fixed
+        run: GOARCH=386 go test ./parquet/file/...