refactored tests and added more

Signed-off-by: Richard Jones <richard@dagger.io>

tests/plan/with/actions.cue

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"alpha.dagger.io/europa/dagger/engine"
+)
+
+engine.#Plan & {
+
+	actions: {
+		image: engine.#Pull & {
+			source: "alpine:3.15.0@sha256:e7d88de73db3d3fd9b2d63aa7f447a10fd0220b7cbf39803c803f2af9ba256b3"
+		}
+
+		verify: engine.#Exec & {
+			input: image.output
+			env: FOO: string
+			args: [
+				"sh", "-c",
+				#"""
+					test -n "$FOO"
+					"""#,
+			]
+		}
+	}
+}

tests/plan/with/params.cue

@@ -0,0 +1,26 @@
+package main
+
+import (
+	"alpha.dagger.io/europa/dagger/engine"
+)
+
+engine.#Plan & {
+	inputs: params: foo: string
+
+	actions: {
+		image: engine.#Pull & {
+			source: "alpine:3.15.0@sha256:e7d88de73db3d3fd9b2d63aa7f447a10fd0220b7cbf39803c803f2af9ba256b3"
+		}
+
+		verify: engine.#Exec & {
+			input: image.output
+			env: FOO: inputs.params.foo
+			args: [
+				"sh", "-c",
+				#"""
+					test "$FOO" = "bar"
+					"""#,
+			]
+		}
+	}
+}