Add docstring for TOML stdlib module (#52834)

Author: jam-khan

base/docs/temp.cpp

@@ -1,5 +1,10 @@
 # This file is a part of Julia. License is MIT: https://julialang.org/license
 
+"""
+`Base.TOML` is an undocumented internal part of Julia's TOML parser
+implementation.  Users should call the the documented interface in the
+TOML.jl standard library instead (by `import TOML` or `using TOML`).
+"""
 module TOML
 
 using Base: IdSet

base/toml_parser.jl

@@ -1,5 +1,10 @@
 # This file is a part of Julia. License is MIT: https://julialang.org/license
 
+"""
+TOML.jl is a Julia standard library for parsing and writing TOML v1.0 files.
+This module provides functions to parse TOML strings and files into Julia data structures
+and to serialize Julia data structures to TOML format.
+"""
 module TOML
 
 module Internals

stdlib/TOML/src/TOML.jl

@@ -27,7 +27,5 @@ include("parse.jl")
 @inferred TOML.parse("foo = 3")
 
 @testset "Docstrings" begin
-    undoc = Docs.undocumented_names(TOML)
-    @test_broken isempty(undoc)
-    @test undoc == [:TOML]
+    @test isempty(Docs.undocumented_names(TOML))
 end