LSP version of extension not present in Maven directory

[toinehartman]

Describe the bug

Currently, the LSP checks and runs DSL projects against its embedded LSP version (in https://github.com/usethesource/rascal-language-servers/blob/fix/simplify-fact-computation/rascal-lsp/pom.xml). This version does not necessarily exist in the local Maven repository (which is only modified based on the project's pom.xml, which might have a different version).

This leads to strange behaviour and missing file errors.

To Reproduce

Steps to reproduce the behavior:

1. Create a project where the rascal-lsp version is different than the version of the current extension.
2. Clear the rascal-lsp JARs in the local Maven repo.
3. Open & type-check the project.
4. Observe errors.

Expected behavior
No errors. The extension should make sure that specific version exists and download it otherwise.

Desktop (please complete the following information):

• Context: VS Code extension
• Rascal Version: rascal-lsp 0.13.2

[DavyLandman]

This is caused by the mvn uri's inside the released jar. they are correct, but then refer to something in maven that doesn't exit yet, as the PathConfig code has avoided downloading the rascal-lsp dependency, since it was on the classpath, and rascal-lsp is specialized.

In a way it's the same problem as why std:/// exists, and this is a case where lib://rascal-lsp was hiding the actual bug.