`Interpolations.gradient` is not allocation free under Julia v1.11

[lmh91]

Interpolations.gradient causes some allocations under Julia v1.11 whereas under Julia v1.10 it does not.
Resulting in also some significant performance drop.

MWE:

using BenchmarkTools
using Interpolations

itp = interpolate(rand(11, 11), BSpline(Cubic()))
x, y = 3.4, 5.3

@btime Interpolations.gradient($itp, $x, $y)

Julia v1.10: 18.136 ns (0 allocations: 0 bytes)

Julia v1.11: 118.716 ns (8 allocations: 384 bytes)

I am not sure if this actually bolongs here or to some dependency or Julia itself.

[bclyons12]

I see this issue as well. Any insights?

[mkitti]

I will need to investigate this further. I just started testing Julia 1.11 in production in a few cases.

[bclyons12]

Making @orso82 aware