Add tests on docker.#Dockerfile

Signed-off-by: Vasek - Tom C <tom.chauveau@epitech.eu>

pkg/universe.dagger.io/docker/test/build-dockerfile-input.cue

@@ -0,0 +1,34 @@
+package test
+
+import (
+	"dagger.io/dagger"
+	"dagger.io/dagger/engine"
+	"universe.dagger.io/docker"
+)
+
+dagger.#Plan & {
+	inputs: directories: testdata: path: "./testdata"
+
+	actions: {
+		image: docker.#Build & {
+			steps: [
+				docker.#Dockerfile & {
+					input: rootfs: inputs.directories.testdata.contents
+				},
+				docker.#Run & {
+					always: true
+					script: """
+						hello >> /test.txt
+						"""
+				},
+			]
+		}
+
+		verify: engine.#ReadFile & {
+			input: image.output.rootfs
+			path:  "/test.txt"
+		} & {
+			contents: "hello world"
+		}
+	}
+}