Do not register all proposed features
Do not register all proposed features

Instead only opt-in to CallHierarchy since it has a vscode API but LSP support
is still proposed.

Discovered while working on SemanticTokens which does not have a vscode API
and is still in the proposed state. Somehow enabling it would crash the
language server.

See https://github.com/microsoft/vscode-languageserver-node/issues/572

rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer,rust-analyzer/rust-analyzer