tests: migrate ops test to bats

Signed-off-by: Andrea Luzzardi <aluzzardi@gmail.com>

tests/ops/mounts/valid/component/main.cue

@@ -0,0 +1,35 @@
+package testing
+
+test: {
+	string
+
+	#up: [
+		{
+			do: "load"
+			from: [{do: "fetch-container", ref: "alpine"}]
+		},
+		{
+			do: "exec"
+			args: ["sh", "-c", """
+					cat /mnt/test/lol > /out
+				"""]
+			mount: "/mnt/test": from: #up: [
+				{
+					do:  "fetch-container"
+					ref: "alpine"
+				},
+				{
+					do: "exec"
+					args: ["sh", "-c", """
+						echo -n "hello world" > /lol
+						"""]
+				},
+			]
+		},
+		{
+			do:     "export"
+			source: "/out"
+			format: "string"
+		},
+	]
+}