Should update to the latest Jetty 11

Currently, I am trying to create a template project for a servlet container.

https://github.com/hantsy/jakartaee9-servlet-starter-boilerplate

But I encountered issues when integrating Weld with Eclipse Jetty.

Some instructions in the doc did not work on the latest Jetty.

https://docs.jboss.org/weld/reference/latest/en-US/html/environments.html#_jetty

1. The following class not found?
``` 
<Arg>-org.eclipse.jetty.util.Decorator</Arg>
```

2. Duplicated id error caused by in the following config when deploying it to Jetty.

```
 <Configure id="webAppCtx" class="org.eclipse.jetty.webapp.WebAppContext">
<New id="BeanManager" class="org.eclipse.jetty.plus.jndi.Resource">
<Arg> <Ref id="webAppCtx"/> </Arg>
```
The `<Ref id="webAppCtx"/>` should be `<Ref refid="webAppCtx"/>`.

I also tried to run external deployMode to run the application on Jetty 11 via Jetty maven plugin, but failed.

https://github.com/hantsy/jakartaee9-servlet-starter-boilerplate/issues/1