Adding Markdown Support.

[Hakureirm]

This PR includes changes to add Markdown support to 'text_to_img.py' and update the Dockerfile, as well as changes to the apt installation file and pip requirements file and font files. All changes have been successfully tested in Docker.

[lss233]

在 Windows 下启动出现如下报错：
关联 issue： Python-Markdown/markdown#1132

D:\quickstart-windows-amd64\chatgpt\python3.9\python.exe D:\quickstart-windows-amd64\chatgpt-mirai-qq-bot\bot.py 
Traceback (most recent call last):
  File "D:\quickstart-windows-amd64\chatgpt-mirai-qq-bot\bot.py", line 26, in <module>
    from utils.text_to_img import to_image
  File "D:\quickstart-windows-amd64\chatgpt-mirai-qq-bot\utils\text_to_img.py", line 6, in <module>
    import markdown
  File "D:\quickstart-windows-amd64\chatgpt\python3.9\lib\site-packages\markdown\__init__.py", line 22, in <module>
    from .core import Markdown, markdown, markdownFromFile
  File "D:\quickstart-windows-amd64\chatgpt\python3.9\lib\site-packages\markdown\core.py", line 27, in <module>
    from .preprocessors import build_preprocessors
  File "D:\quickstart-windows-amd64\chatgpt\python3.9\lib\site-packages\markdown\preprocessors.py", line 29, in <module>
    from .htmlparser import HTMLExtractor
  File "D:\quickstart-windows-amd64\chatgpt\python3.9\lib\site-packages\markdown\htmlparser.py", line 31, in <module>
    spec.loader.exec_module(htmlparser)
AttributeError: 'zipimporter' object has no attribute 'exec_module'
2023-02-24 01:12:44.213 | INFO     | chatbot:conversation_remover:101 - 删除会话中……

Process finished with exit code 1

已修复。

[acai66]

询问markdown语法时，有这一段图片样例，在渲染为html时报错：提示图片URL加载失败

[acai66]

保险起见，又加入了之前的text_to_image函数，在markdown渲染失败时，调用之前的文本转图片函数。

[lss233]

保险起见，又加入了之前的text_to_image函数，在markdown渲染失败时，调用之前的文本转图片函数。

我觉得这样很不错

[acai66]

供参考，不提pr
text_to_img.zip

[lss233]

供参考，不提pr text_to_img.zip

好的，那就由我来进行一个合并

[lss233]

搞定了，感谢两位

[acai66]

不清楚你们有没有单行代码过长被截断的情况

[Hakureirm]

不清楚你们有没有单行代码过长被截断的情况

出现过。代码块应该是可以改成超出原设定宽度后，自适应宽度的，之前测试它自己渲染来自URL的图片时就自动做到了，不过我没学过前端，不知道具体是改哪里。

[lss233]

这个开个 issue 跟一下