feat(lsp): added config for systemd-language-server

https://github.com/psacawa/systemd-language-server

lua/plugins/lsp/config/systemd.lua

@@ -0,0 +1,28 @@
+---@type LazySpec
+return {
+  "AstroNvim/astrolsp",
+  cond = vim.fn.executable("systemd-language-server") == 1,
+  ---@param opts AstroLSPOpts
+  opts = function(_, opts)
+    opts.servers = opts.servers or {}
+    table.insert(opts.servers, "systemd_ls")
+    opts.config = require("astrocore").extend_tbl(opts.config or {}, {
+      systemd_ls = {
+        cmd = { "systemd-language-server" },
+        filetypes = { "systemd" },
+        root_dir = function() return nil end,
+        single_file_support = true,
+        settings = {},
+        docs = {
+          description = [[
+https://github.com/psacawa/systemd-language-server
+Language Server for Systemd unit files.
+
+I tested it with python 3.10.15
+3.12.7 didn't work
+]],
+        },
+      },
+    })
+  end,
+}