Add compat with HistoricalStdlibVersions v2

This fixes support for nightly with the new Pkg version:
JuliaLang/Pkg.jl#3911.

Project.toml

@@ -41,7 +41,7 @@ Bzip2_jll = "1.0.8"
 CodecZlib = "0.5, 0.6, 0.7"
 Downloads = "1.5"
 Gzip_jll = "1.12.0"
-HistoricalStdlibVersions = "0.1, 1"
+HistoricalStdlibVersions = "2"
 InteractiveUtils = "1.7"
 JLLWrappers = "1.4"
 JSON = "0.21"

src/BinaryBuilderBase.jl

@@ -4,7 +4,7 @@ using Pkg, Pkg.Artifacts, Random, Libdl, InteractiveUtils
 using Base.BinaryPlatforms
 using Downloads
 using JSON, OutputCollectors, Scratch
-using HistoricalStdlibVersions
+import HistoricalStdlibVersions
 
 # Re-export useful stuff from Base.BinaryPlatforms:
 export HostPlatform, platform_dlext, valid_dl_path, arch, libc,
@@ -222,8 +222,8 @@ function __init__()
  use_ccache[] = true
  end
 
- # Populate `Pkg.Types.STDLIBS_BY_VERSION`
- append!(empty!(Pkg.Types.STDLIBS_BY_VERSION), HistoricalStdlibVersions.STDLIBS_BY_VERSION)
+ # Populate `Pkg.Types.STDLIBS_BY_VERSION`.
+ HistoricalStdlibVersions.register!()
 end