Test checking allocation of using an integer or mutable as key in Dict sometimes fail on CI

[KristofferC]

The test in

julia/Compiler/test/codegen.jl

Lines 390 to 412 in 40fbc88

	# Issue #10208 - Unnecessary boxing for calling objectid
	struct FooDictHash{T}
	x::T
	end
	function f_dict_hash_alloc()
	d = Dict{FooDictHash{Int},Int}()
	for i in 1:10000
	d[FooDictHash(i)] = i+1
	end
	d
	end
	function g_dict_hash_alloc()
	d = Dict{Int,Int}()
	for i in 1:10000
	d[i] = i+1
	end
	d
	end
	# Warm up
	f_dict_hash_alloc(); g_dict_hash_alloc();
	@test abs((@allocated f_dict_hash_alloc()) / (@allocated g_dict_hash_alloc()) - 1) < 0.1 # less that 10% difference

seems to be a bit flaky. Errored on CI (https://buildkite.com/julialang/julia-release-1-dot-12/builds/10#0194fe6a-8efc-4a90-af48-f19bc8aa1161) with:

julia/Compiler/test/codegen.jl:412 =# @allocated(g_dict_hash_alloc()) - 1) < 0.1
--
  | Evaluated: 0.16517549896765304 < 0.1

Test introdocued in #31771. Modified in #55223.

cc @Keno, @d-netto.