Check new LSP features

[albilu]

Configurations
Add extendSelect option to flake8 plugin.

• pylsp.plugins.flake8.extendSelect | array of string items | List of errors and warnings to append to select list. | []

Allow Jedi's extra_paths to be placed in front of sys.path.

• pylsp.plugins.jedi.prioritize_extra_paths | boolean | Whether to place extra_paths at the beginning (true) or end (false) of sys.path | false

LSP hooks
Add support for window/logMessage.
Add version support to workspace/publishDiagnostics.
Support initializationOptions to configure the server.
Add new pylsp_workspace_configuration_changed hookspec so that plugins can react when client sends a configuration change to the server.

[albilu]

no need to update settings. additionalProperties already allowed