`about(::Module)` throws exception when module exports undefined name

Calling about on a module with an undefined exported name results in an exception.

julia> module Temp
       export notdefined
       end
Main.Temp

julia> about(Temp)
Module Main.Temp
ERROR: UndefVarError: `notdefined` not defined
Stacktrace:
  [1] (::About.var"#classify#24"{Module})(m::Module, name::Symbol)
    @ About ~/.julia/packages/About/52iMk/src/values.jl:136
[...]

Version info:

Julia Version 1.10.4
Commit 48d4fd48430 (2024-06-04 10:41 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 32 × 13th Gen Intel(R) Core(TM) i9-13900KF
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-15.0.7 (ORCJIT, goldmont)
Threads: 32 default, 0 interactive, 16 GC (on 32 virtual cores)
Environment:
  JULIA_NUM_THREADS = auto
  JULIA_EDITOR = code

tecosaur / About.jl

`about(::Module)` throws exception when module exports undefined name #27