Create a mock client and server able to test the command and queries

[cmoulliard]

TODO

Create a mock client and server similar to what this project did
https://github.com/eclipse-lemminx/lemminx/tree/main/org.eclipse.lemminx/src/test/java/org/eclipse/lemminx able to test the RuleEntry command and the queries to search about: java annotation, method, field, etc

[konveyor-ci-bot]

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[shawn-hurley]

Seeing as you have a Pr up
For this don't mind if I add you as an assignee?