ent/ci: install goimports before running tests

Summary: Pull Request resolved: https://github.com/facebookincubator/ent/pull/16

Reviewed By: alexsn

Differential Revision: D16914392

fbshipit-source-id: 7f0fc01fb760b0712341810796d6539f549a9b5f

entc/integration/compose/Dockerfile

@@ -0,0 +1,19 @@
+# Multi stage application builder
+FROM golang:1.12.9-alpine
+
+# Install tools required to build the project
+RUN apk add --no-cache git gcc musl-dev
+
+# Use public go modules proxy
+ENV GOPROXY https://proxy.golang.org
+
+# Install goimports for entc.
+RUN go get -u golang.org/x/tools/cmd/goimports
+
+# Copy mod files and install dependencies.
+WORKDIR /ent
+COPY go.mod go.sum ./
+RUN go mod download
+
+# Copy project.
+COPY . ./