universe: spin out alpine tests

Signed-off-by: Solomon Hykes <solomon@dagger.io>

stdlib/.dagger/env/alpine/plan/alpine.cue

@@ -0,0 +1,44 @@
+package alpine
+
+import (
+	"dagger.io/alpine"
+	"dagger.io/dagger/op"
+)
+
+TestImageVersion: {
+	image: alpine.#Image & {
+		// install an old version on purpose
+		version: "3.10.9"
+	}
+
+	test: #up: [
+		op.#Load & {from: image},
+		op.#Exec & {
+			args: [
+				"sh",
+				"-ec",
+				"""
+					test "$(cat /etc/alpine-release)" = 3.10.9
+					""",
+			]
+		},
+	]
+}
+
+TestPackageInstall: {
+	image: alpine.#Image & {
+		package: jq:   true
+		package: curl: true
+		version: "3.13"
+	}
+
+	test: #up: [
+		op.#Load & {from: image},
+		op.#Exec & {
+			args: ["jq", "--version"]
+		},
+		op.#Exec & {
+			args: ["sh", "-ec", "curl --version"]
+		},
+	]
+}