Draft: (paused) Use workspace for Cargo.toml files

Cargo provides a workspace feature (book, reference). We can use it to avoid repetition.

end2end-tests/Cargo.toml

 [package]
+description = 'duniter end2end tests.'
 name = 'duniter-end2end-tests'
 edition.workspace = true
 authors.workspace = true
-description.workspace = true
 license.workspace = true
 repository.workspace = true
 documentation.workspace = true