🤖 Bump the Pkg stdlib from e476cd0c to 39cc95a6

[DilumAluthgeBot]

Stdlib: Pkg
Branch: master
Old commit: e476cd0c
New commit: 39cc95a6
Bump invoked by: @IanButterworth

$ git log --oneline e476cd0c..39cc95a6
39cc95a6 Extend install prompt functionality (#2669)
d037cee6 Missing package install prompt: Strip any rogue spaces from user input (#2675)
5bbfef6a Make `write_env_usage` atomic (#2661)
baec70b9 instantiate: don't update the registry if no env deps exist (#2660)
cb9441fa [docs] add "Creating and maintaining registries" (#2659)
90b535df Delete the `Pkg.Versions.:≳` function (#2658)
67ed9cb3 download/unpack: some code cleanup (#2641)