微信小程序点击复制文本到剪切板，获取剪切板内容
设置剪切板：wx.setClipboardData获取剪切板：wx.getClipboardDataapi:https://developers.weixin.qq.com/miniprogram/dev/api/device/clipboard/wx.setClipboardData.htmlwxml:<view>内容：{{contents}} </view><view bindtap='copyText' data-te
