BUG: Issue with chat ui because of gradio when using apache vhost as reverse proxy

[AndiMajore]

Describe the bug

We encountered a bug when serving Xinference (since 0.8.5 & through docker) through an apache vhost with reverse proxy configuration. Issue is the dynamic resolution of paths (through gradio>=4.0.0) in the chat ui. URLs pointing to http://$HOST/$MODEL_ID/info and http://$HOST/$MODEL_ID/theme.css will be instead resolved as http://$HOST/info and http://$HOST/theme.css. This makes the chat ui unusable when served through an apache vhost.

The issue was introduced with commit #983, removing the hard requirement of gradio<4.0.0.

To Reproduce

1. Launch latest (0.10.0) Xinference docker image.

2. Install apache vhost and configure reverse proxy:

   
   <VirtualHost *:80>
    ServerName $server_name
   
    #default proxy via internal port
    ProxyPreserveHost On
   
    RewriteEngine on
    RewriteCond %{HTTP:Upgrade} =websocket [NC]
    RewriteCond %{REQUEST_URI} ^/
    RewriteRule /(.*) ws://localhost:9997/$1 [P,L]
   
    RewriteRule ^/(.*)$ http://127.0.0.1:9997/$1 [P]
   
    Header always set Content-Security-Policy: upgrade-insecure-requests
   
    HostnameLookups Off
   
    UseCanonicalName Off
   
    ServerSignature On
   
   <Directory />
    AllowOverride None
    Options -Indexes
   </Directory>
    TraceEnable off
   
    Errorlog /usr/share/apache2/log/llm/llm-error.log
    CustomLog /usr/share/apache2/log/llm/llm-access.log combined

3. Launch a model in the UI
4. Open chat UI
5. 
![image](https://github.com/xorbitsai/inference/assets/18685571/2445ce2f-d32d-4b0f-af9d-c3306394f02b)

### To Fix
I created a derived version of the official Xinference docker image as follows:

```Dockerfile
FROM xprobe/xinference:latest
RUN pip install gradio==3.50.2

Repeating step 1.-4. for this docker image will result in a working chat UI.

Therefore I propose to fix the gradio dependency to 3.50.2.

[qinxuye]

@ChengjieLi28 Do you think it's reasonable to fix the gradio version for docker build?