fix(treesitter): remove deleted jsonc parser (#6848)

## Description

d2350758b3
removed parsers not hosted on Github, `jsonc` among them. Remove it from
LazyVim as well. On a fresh new installation, there's no problem and it
doesn't even install, but on existing installation you get an error when
updating about parser not available.

<img width="2559" height="313" alt="2025-12-07_11-24"
src="https://github.com/user-attachments/assets/99802b66-ff39-4631-89c6-ee4f2516acf1"
/>

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## Related Issue(s)
None
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## Checklist

- [x] I've read the
[CONTRIBUTING](https://github.com/LazyVim/LazyVim/blob/main/CONTRIBUTING.md)
guidelines.

lua/lazyvim/plugins/treesitter.lua

@@ -37,7 +37,6 @@ return {
         "javascript",
         "jsdoc",
         "json",
-        "jsonc",
         "lua",
         "luadoc",
         "luap",