move Pkg out of the sysimage (take 2)

[KristofferC]

Will make Pkg latency bad until Pkg gets bumped to a version that includes JuliaLang/Pkg.jl#3447. But that will happen quickly after this.

[KristofferC]

Saw this in a CI log:

From worker 7:	[ Info: Downloading General registry from https://pkg.julialang.org/registry/23338594-aafe-5451-b93e-139f81909106/66bef8cf57a2e1577a0abe96bcdd6af428e32a09
--
  | Downloads       (5) \|    81.79 \|   0.19 \|  0.2 \|     313.65 \|   763.83
  | From worker 7:	Username for 'https://github.com': Username for 'https://github.com': fatal: could not read Username for 'https://github.com': terminal prompts disabled
  | From worker 7:	fatal: could not read Username for 'https://github.com': terminal prompts disabled
  | From worker 7:	┌ Warning: Module Pkg with build ID fafbfcfd-c349-1155-0028-7791162e4a28 is missing from the cache.
  | From worker 7:	│ This may mean Pkg [44cfe95a-1eb2-52ea-b672-e2afdf69b78f] does not support precompilation but is imported by a module that does.
  | From worker 7:	└ @ Base loading.jl:1942

[KristofferC]

Seems like the RR CI gets stuck in Pkg tests:

From worker 7:	Username for 'https://github.com': Username for 'https://github.com': fatal: could not read Username for 'https://github.com': terminal prompts disabled
--
  | From worker 7:	fatal: could not read Username for 'https://github.com': terminal prompts disabled
  | From worker 7:	┌ Warning: Module Pkg with build ID fafbfcfd-be0a-a1a0-0028-7dc751824a03 is missing from the cache.
  | From worker 7:	│ This may mean Pkg [44cfe95a-1eb2-52ea-b672-e2afdf69b78f] does not support precompilation but is imported by a module that does.
  | From worker 7:	└ @ Base loading.jl:1942
  |  
  |  
  | Process failed to exit within 2700s, requesting termination (SIGTERM) of PID 383.
  |  
  |  
  | Sent SIGTERM to PID 383.
  |  
  | [395] signal (15): Terminated
  | in expression starting at none:1
  | unknown function (ip: 0x70000002)
  | unknown function (ip: 0x7fee6d93f2c3)
  | traced_raw_syscall at /workspace/srcdir/rr/src/preload/syscallbuf.c:338
  | syscall_hook at /workspace/srcdir/rr/src/preload/syscallbuf.c:3942 [inlined]
  | syscall_hook at /workspace/srcdir/rr/src/preload/syscallbuf.c:3926
  | unknown function (ip: 0x7fee6d939312)
  | unknown function (ip: 0x7fee6d93937c)
  | unknown function (ip: 0x7fee6d939398)
  | epoll_wait at /lib/x86_64-linux-gnu/libc.so.6 (unknown line)
  | uv__io_poll at /workspace/srcdir/libuv/src/unix/epoll.c:236
  | uv_run at /workspace/srcdir/libuv/src/unix/core.c:400
  | ijl_task_get_next at /cache/build/default-amdci4-3/julialang/julia-master/src/partr.c:469
  | From worker 7:
  | From worker 7:	[554] signal (15): Terminated
  | From worker 7:	in expression starting at /cache/build/default-amdci4-2/julialang/julia-master/julia-4fd10b97fd/share/julia/stdlib/v1.11/Pkg/test/binaryplatforms.jl:13

[vtjnash]

This seems quite epic, and a good milestone for Julia

[oscardssmith]

how big of an effect does this have on sysimage size?