improve apply_type error message

[vtjnash]

Fixes #42401

[vtjnash]

Ah, wait, was this a bad idea:

julia> struct X{T, A<:T} end

julia> X{1, 1}
ERROR: TypeError: in TypeVar, in upper bound, expected Type, got a value of type Int64
Stacktrace:
 [1] top-level scope
   @ REPL[2]:1

previously:

julia> X{1, 1}
ERROR: TypeError: in X, in A, expected A<:T, got a value of type Int64
Stacktrace:
 [1] top-level scope
   @ REPL[2]:1