Code completion is not working on macOS

# Issue information

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## BUG report

### Environment

- Apache Camel LSP Client Extensions Plugin version: **1.0.0.201910110736**
- Eclipse IDE 2019-03 (4.11.0)
- OS:
- [ ] Linux (*RHEL*, *Fedora*, *Ubuntu*, ...)
- [ ] Windows
- [x] macOS

### Description of wrong behavior

- Empty content assistant for code completion on macOS. Tried inside XML and Java editors.

### Exact steps to reproduce issue

1. open file with camel-context (e.g. xml or java syntax)
2. try to invoke code completion for e.g. ``````
3. empty content assistant