Restrict kwarg type in code generated by @non_differentiable macro

[oxinabox]

Fixes all the method ambiguities reported in ChainRules CI for julia 1.10

julia> filter(Test.detect_ambiguities(ChainRules, ChainRulesCore)) do t
   (t[1].name in [:rrule, Symbol("rrule##kw")])
end
Tuple{Method, Method}[]

closes JuliaDiff/ChainRules.jl#777

[oxinabox]

Yay for first time in ages IntegrationTest / ChainRules.jl (pull_request) Successful in 24m

[ToucheSir]

LGTM if any reviewer works for you. I'm pleasantly surprised this works all the way back to 1.6.

[oxinabox]

LGTM if any reviewer works for you.

BlueStyle basically says at least 1 person with merge rights needs to be involved in the PR. So if that author has merge rights, the reviewer doesn't have to (and visa versa)

TY.