`ipython_mode` breaks the ability to load a package and use macros in a single input

[wangl-cc]

When ipython_mode is enabled, it becomes impossible to load a package and use macros provided by that package in a single input in the REPL. For example, attempting to use the @btime macro from the BenchmarkTools package in this way will result in an error:

In [1]: using BenchmarkTools; @btime 1
ERROR: LoadError: UndefVarError: `@btime` not defined
in expression starting at REPL[1]:1

However, this same operation will work correctly in a normal REPL:

julia> using BenchmarkTools; @btime 1
  0.833 ns (0 allocations: 0 bytes)
1

Version

Julia Version 1.9.0-rc1
Commit 3b2e0d8fbc1 (2023-03-07 07:51 UTC)
Platform Info:
  OS: macOS (arm64-apple-darwin21.4.0)
  CPU: 8 × Apple M1
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-14.0.6 (ORCJIT, apple-m1)
  Threads: 1 on 4 virtual cores