feat: update to go modules

vendor/github.com/alecthomas/chroma/formatters/json.go

@@ -1,31 +0,0 @@
-package formatters
-
-import (
-	"encoding/json"
-	"fmt"
-	"io"
-
-	"github.com/alecthomas/chroma"
-)
-
-// JSON formatter outputs the raw token structures as JSON.
-var JSON = Register("json", chroma.FormatterFunc(func(w io.Writer, s *chroma.Style, it chroma.Iterator) error {
-	fmt.Fprintln(w, "[")
-	i := 0
-	for t := it(); t != chroma.EOF; t = it() {
-		if i > 0 {
-			fmt.Fprintln(w, ",")
-		}
-		i++
-		bytes, err := json.Marshal(t)
-		if err != nil {
-			return err
-		}
-		if _, err := fmt.Fprint(w, "  "+string(bytes)); err != nil {
-			return err
-		}
-	}
-	fmt.Fprintln(w)
-	fmt.Fprintln(w, "]")
-	return nil
-}))