decoder_test: Readd nfkd test

Author: tgallice

stringutil/decoder_test.go

@@ -43,6 +43,11 @@ func TestDecodeToASCII(t *testing.T) {
 			in:  "Collaboration: 𝕸𝖎𝖆𝖒𝖎 🌞 x KiwiKurve",
 			out: "Collaboration: x KiwiKurve",
 		},
+		{
+			in:   "Collaboration: 𝕸𝖎𝖆𝖒𝖎 🌞 x KiwiKurve",
+			out:  "Collaboration: Miami x KiwiKurve",
+			opts: nfkd,
+		},
 		{
 			in:  "back soon ✌🏽📍ashleyrchand@gmail.com",
 			out: "back soon ashleyrchand@gmail.com",