remove repetitive words (#29695)

Signed-off-by: pengqiseven <912170095@qq.com>

routers/api/v1/repo/issue.go

@@ -368,7 +368,7 @@ func ListIssues(ctx *context.APIContext) {
 	//   required: false
 	// - name: created_by
 	//   in: query
-	//   description: Only show items which were created by the the given user
+	//   description: Only show items which were created by the given user
 	//   type: string
 	// - name: assigned_by
 	//   in: query