chore: update config defaults in readme (#641)

Co-authored-by: tjex <tjex@tjex.net>

Author: AntoineGS

README.md

@@ -159,7 +159,7 @@ require('copilot').setup({
     file = vim.fn.stdpath("log") .. "/copilot-lua.log",
     file_log_level = vim.log.levels.OFF,
     print_log_level = vim.log.levels.WARN,
-    trace_lsp = "off", -- "off" | "messages" | "verbose"
+    trace_lsp = "off", -- "off" | "debug" | "verbose"
     trace_lsp_progress = false,
     log_lsp_messages = false,
   },