[REPL] world age mistake in handling Pkg extension for paste

[vtjnash]

Doing a paste that included the pkg> prompt crashed with the following backtrace

(tempproj) pkg> activate --temp                                                                                        
                                                                                                                       
┌ Error: Error in the keymap                                                                                                                                                                                                                  
│   exception =                                                                                                        
│    MethodError: no method matching (::REPLExt.var"#repl_init##0#repl_init##1"{REPL.LineEdit.Prompt})(::REPL.LineEdit.MIState, ::REPL.LineEditREPL, ::String)                                                                                
│    The applicable method may be too new: running in world age 23761, while current world is 23781.                   
│                                                                                                                                                                                                                                             
│    Closest candidates are:                                                                                           
│      (::REPLExt.var"#repl_init##0#repl_init##1")(::Any, ::Any...) (method too new to be called from this world context.)                                                                                                                    
│       @ REPLExt ~/julia1/usr/share/julia/stdlib/v1.12/Pkg/ext/REPLExt/REPLExt.jl:176                                 
│                                                                                                                      
│    Stacktrace:                                           
│     [1] (::REPL.var"#setup_interface##32#setup_interface##33"{Regex, Regex, Int64, Int64, REPL.LineEdit.Prompt, REPL.LineEdit.Prompt, REPL.LineEdit.Prompt})(::REPL.LineEdit.MIState, ::Any, ::Vararg{Any})                                 
│       @ REPL ~/julia1/usr/share/julia/stdlib/v1.12/REPL/src/REPL.jl:1538                                             
│     [2] #invokelatest#1                                                                                              
│       @ ./essentials.jl:1056 [inlined]                                                                               
│     [3] invokelatest                                                                                                 
│       @ ./essentials.jl:1052 [inlined]                   
│     [4] (::REPL.LineEdit.var"#match_input##0#match_input##1"{REPL.var"#setup_interface##32#setup_interface##33"{Regex, Regex, Int64, Int64, REPL.LineEdit.Prompt, REPL.LineEdit.Prompt, REPL.LineEdit.Prompt}, String})(s::Any, p::Any)     
│       @ REPL.LineEdit ~/julia1/usr/share/julia/stdlib/v1.12/REPL/src/LineEdit.jl:1756                                
│     [5] macro expansion                                                                                              
│       @ ~/julia1/usr/share/julia/stdlib/v1.12/REPL/src/LineEdit.jl:2906 [inlined]                                    
│     [6] macro expansion                                  
│       @ ./lock.jl:376 [inlined]                          
│     [7] (::REPL.LineEdit.var"#prompt!##2#prompt!##3"{REPL.Terminals.TTYTerminal, REPL.LineEdit.ModalInterface, REPL.LineEdit.MIState, ReentrantLock, REPL.LineEdit.Prompt})()                                                               
│       @ REPL.LineEdit ~/julia1/usr/share/julia/stdlib/v1.12/REPL/src/LineEdit.jl:2896                                
└ @ REPL.LineEdit ~/julia1/usr/share/julia/stdlib/v1.12/REPL/src/LineEdit.jl:2908