Re-translate the Japanese version (#1871)

* Retranslate Japanese docs with GPT-5.4

* Retranslate Japanese code with GPT-5.4

ja/codes/go/chapter_graph/graph_dfs_test.go

@@ -0,0 +1,28 @@
+// File: graph_dfs_test.go
+// Created Time: 2023-02-18
+// Author: Reanon (793584285@qq.com)
+
+package chapter_graph
+
+import (
+	"fmt"
+	"testing"
+
+	. "github.com/krahets/hello-algo/pkg"
+)
+
+func TestGraphDFS(t *testing.T) {
+	/* 無向グラフを初期化 */
+	vets := ValsToVets([]int{0, 1, 2, 3, 4, 5, 6})
+	edges := [][]Vertex{
+		{vets[0], vets[1]}, {vets[0], vets[3]}, {vets[1], vets[2]},
+		{vets[2], vets[5]}, {vets[4], vets[5]}, {vets[5], vets[6]}}
+	graph := newGraphAdjList(edges)
+	fmt.Println("初期化後、グラフは:")
+	graph.print()
+
+	/* 深さ優先探索 */
+	res := graphDFS(graph, vets[0])
+	fmt.Println("深さ優先探索（DFS）の頂点列:")
+	PrintSlice(VetsToVals(res))
+}