feat!: default profile set to border-fused+hide

To restore the old default:
```lua
require("fzf-lua").setup({
    { "default-title" },
    -- rest of setup options
})
```

Author: ibhagwan

lua/fzf-lua/profiles/default.lua

@@ -1,4 +1,4 @@
 return {
   desc = "fzf-lua default options",
-  "default-title",
+  { "border-fused", "hide" },
 }

lua/fzf-lua/test/helpers.lua

@@ -131,6 +131,7 @@ M.new_child_neovim = function()
   child.setup = function(config)
     local lua_cmd = ([[
       require("fzf-lua").setup(vim.tbl_deep_extend("keep", ..., {
+        { "default-title" },
         %s
         winopts = {
           on_create = function(e)