## What is this PR for?
After recent changes in `rustaceanvim` in
https://github.com/mrcjkb/rustaceanvim/pull/403, `checkOnSave` is
supposed to be boolean and the table that we were passing to
`checkOnSave` previously should be passed to `check` instead. I left the
`check` table undefined, because the options that we were passing to
`checkOnSave` before are the default ones being passed to `check`. So,
only if the user wants to change something should he change the values
of the `check` table according to what he wants.
## Does this PR fix an existing issue?
No
## Checklist
- [x] I've read the
[CONTRIBUTING](https://github.com/LazyVim/LazyVim/blob/main/CONTRIBUTING.md)
guidelines.
fix this warning
```
Warn 11:52:45 PM notify.warn nvim-lspconfig.rust_analyzer has been setup.
This will likely lead to conflicts with the rustaceanvim LSP client.
See ':h rustaceanvim.mason'
```
fix taken from https://github.com/mrcjkb/rustaceanvim/blob/master/doc/mason.txt
According to the maintainer of `rustaceanvim` (see his comment [here](https://github.com/LazyVim/LazyVim/pull/2198#issuecomment-1999475044)) he says
> To pick up on this: There's a good reason rustaceanvim doesn't automatically pick up a mason.nvim installation. It will most likely be built with a different toolchain than the one your project uses, often leading to discrepancies and subtle bugs.
It's easy to configure rustaceanvim to use mason.nvim if you really want it, but I generally adhere to the YAGNI principle.
I tried locally and the removal of `rust-analyzer` from `nvim-lspconfig` doesn't
seem to have any effect on how `rustaceanvim` behaves.
I propose to remove all instances of `rust-analyzer` from `nvim-lspconfig` to avoid
any possible issues from users that don't have `rust-analyzer` installed
in their toolchain (in this case it would pick up Mason's $PATH I
believe), since they will think that since `rust-analyzer` is installed
by Mason, there shouldn't be a problem and report issues as bugs.
For example, 'buffer' source by default has group_index = 2 [1], however
if we take all the sources plus crates and run them through
cmp.config.sources() again, since it's a one-dimensional list, all
group_indexes will be reset to 1.
[1] 879e29504d/lua/lazyvim/plugins/coding.lua (L74-L80)
