Base: avoid losing Method provenance in `@deprecate` (#61931)

Improves stacktraces and `methods(...)` queries for any Methods defined
through `@deprecate`:

```julia
julia> @deprecate foo(x::Int) rand(x)
foo (generic function with 1 method)

julia> methods(foo)
 [1] foo(x::Int64)
     @ REPL[3]:1
```

versus before:

```julia
julia> methods(foo)
 [1] foo(x::Int64)
     @ deprecated.jl:215
```