Add and remove button don't work for eclipse project

[pl07]

Configuration:

VScode: 1.41.1
JDK: 1.8.0_202
OS: Mac,Win
Java Dependency view version: 0.8.0
Language Support for Java version:0.55.1

Repro Steps:

1. Create an eclipse project and add external jars to library
2. Open in vscode and open dependency explorer

Results:

Add and remove button on referenced libraries don't work, and jars under lib folder won't show.