feat(extras): rego language support

It took a while, but finally we can work with
[OPA](https://www.openpolicyagent.org/) like a BOSS in neovim.

Linking some PR-s that had to land in the past couple of months to make this config as
simple as it is now:
- treesitter commentstring support in JoosepAlviste/nvim-ts-context-commentstring#108
- regols support in nvim-lspconfig: neovim/nvim-lspconfig#2721
- regols support in mason-registry: mason-org/mason-registry#4896
- regols support in mason-lspconfig: williamboman/mason-lspconfig.nvim#403
- regal support in nvim-lspconfig: neovim/nvim-lspconfig#3071
- regal support in mason-registry: mason-org/mason-registry#5717
- regal support in mason-lspconfig: williamboman/mason-lspconfig.nvim#426

Signed-off-by: Zoltán Reegn <[email protected]>

lua/lazyvim/plugins/extras/lang/rego.lua

@@ -0,0 +1,20 @@
+return {
+  recommended = {
+    ft = "rego",
+  },
+  {
+    "neovim/nvim-lspconfig",
+    opts = {
+      servers = {
+        regols = {},
+        regal = {},
+      },
+    },
+  },
+  {
+    "nvim-treesitter/nvim-treesitter",
+    opts = {
+      ensure_installed = { "rego" },
+    },
+  },
+}