Fix typo: invalid comment delimiter in README

[Jumpaku]

In this pull request, I revised {{ /* Go Template */ }} to {{- /* Go Template */ -}} in the README description, aligning it with the content in the screenshot "comment.png".

The original {{ /* Go Template */ }} is considered an invalid comment because there are spaces between {{ and /* or */ and }} according to https://pkg.go.dev/text/template#hdr-Actions

{{/* a comment */}}
{{- /* a comment with white space trimmed from preceding and following text */ -}}
	A comment; discarded. May contain newlines.
	Comments do not nest and must start and end at the
	delimiters, as shown here.

It should be written as {{- /* Go Template */ -}} or {{/* Go Template */}}.
In fact, the following code panics with an error panic: template: comments:1: unexpected "/" in command

package main

import "text/template"

func main() {
	template.Must(template.New("comments").Parse("{{ /* Go Template */ }}"))
}