Import howett.net/plist by its correct name

Also bumping the version to one with a go.mod.

vendor/howett.net/plist/fuzz.go

@@ -0,0 +1,17 @@
+// +build gofuzz
+
+package plist
+
+import (
+	"bytes"
+)
+
+func Fuzz(data []byte) int {
+	buf := bytes.NewReader(data)
+
+	var obj interface{}
+	if err := NewDecoder(buf).Decode(&obj); err != nil {
+		return 0
+	}
+	return 1
+}