`workspace/symbols` doesn't seem to respect workspaces or rootUri / root_dir

Nadie ha tomado este issue todavía.

### How are you using the lua-language-server?

NeoVim

### Which OS are you using?

MacOS

### What is the issue affecting?

Other

### Expected Behaviour

1. Results should only come from the current project, i.e. that rooted at root_dir, or at the very least only come from the listed workspace folders.
2. All symbols appearing in the files named by the above condition should appear in the results (at least, `document/symbols` should be a subset of `workspace/symbols` for any document in the current project)

### Actual Behaviour

1. Most results come outside root_dir; in fact, most results come from outside any workspace folder, meaning that the results are essentially global.
2. Some expected results from within the current workspace don't appear.

For evidence of (1), here's some results from`vim.lsp.buf.workspace_symbol()`:

```
# current project, which matches root_dir and is a configured workspace
lua/neogit/status.lua|653 col 3| [Variable] vim.o.autochdir

# from my nvim config, which is not the current root_dir but is a configured workspace
/Users/neilvyas/.config/nvim/lua/plugins/modes.lua|61 col 9| [Variable] vim.opt.background

# from random lua files anywhere on my system; from outside of root_dir or any workspace
/Users/neilvyas/.local/share/nvim/mason/packages/lua-language-server/libexec/meta/Lua 5.4 en-us utf8/io.lua|171 col 11| [Class] file*

```

For evidence of (2), we can see that `document/symbols` returns results which `workspace/symbols` does not (this is actually what clued me into this being a possible bug). For example, the following result from `document/symbols`, issued from `lua/neogit/status.lua`, does not appear in `workspace/symbols`:

```
lua/neogit/status.lua|506 col 16| [Function] refresh_status_buffer
```

### Reproduction steps

1. Configure lua_ls using the recommended instructions from `mason.nvim` https://github.com/williamboman/mason.nvim#configuration, `mason-lspconfig.nvim` https://github.com/williamboman/mason-lspconfig.nvim, and `lspconfig.nvim` https://github.com/neovim/nvim-lspconfig.
2. Edit a lua buffer.
3. Issue `vim.lsp.buf.workspace_symbol()`

### Additional Notes

You might think that this issue stems from neovim's LSP client; however, the code related to workspace/symbols is so minimal that I doubt the error arises there: https://github.com/neovim/neovim/blob/v0.8.1/runtime/lua/vim/lsp/handlers.lua#L253

From my cursory investigation of lua_ls's implementation, it seems like the issue might be to do with how `allGlobals` is populated, since this is ultimately what populates workspace/symbols: https://github.com/LuaLS/lua-language-server/blob/f836d90eb629c22219cbcdff9bfcd7f45f1751f3/script/vm/global.lua#L209

What follows are selections from the output of `vim.print(vim.lsp.get_client_by_id(1))`, which shows a bunch of data related to how `lua_ls` is configured by and attached to neovim.

Here, you can see that the root_dir is set properly for the current buffer (editing the neogit plugin), and there are workspaces corresponding to the other buffers I have open (the detour.nvim plugin and editing my neovim configuration, which is written in lua):

This seems to be the problem referenced by the only similar issue I found, #1731 , but I think it indicates that, in fact, that issue does not apply any more, and I cannot udnerstand what the resolution in that issue was anyway.

Here, you can see that the workspace related capabilities seem to be setup properly:

### Log File

_No response_

Comienza con la implementación de workspace/symbols y la población de allGlobals mencionada en script/vm/global.lua. Reproduce el problema mediante vim.lsp.buf.workspace_symbol() de Neovim usando la configuración del workspace indicada y, después, compara sus resultados con document/symbols. Se considera terminado cuando los resultados están limitados al ámbito del workspace configurado e incluyen los símbolos encontrados por document/symbols.

Escrito por el modelo de indexación a partir del texto del issue.