InteractiveUtils: avoid side-effect compilation in first @time_imports print

[IanButterworth]

Before, the first dep with an __init__() always showed compilation from just compiling the time_imports tooling

% ./julia --startup-file=no -q
julia> @time_imports using NetworkOptions
               ┌ 0.0 ms NetworkOptions.__init__() 
     15.6 ms  NetworkOptions 75.43% compilation time

This PR

% ./julia --startup-file=no -q                                                                
julia> @time_imports using NetworkOptions
               ┌ 0.0 ms NetworkOptions.__init__() 
      4.6 ms  NetworkOptions

Baking @time_imports into the REPL pkgimage didn't help because something in the package load system was invalidating the multi-arg print methods this avoids (couldn't figure that out).