Fix sortslices rrule inference test failure on Julia 1.12

The ntuple with conditional (Colon vs Vector) produces a union type that
Julia 1.12 can no longer fully narrow, causing inference check failures.
Add check_inferred=false consistent with the existing 3D test case.

Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com>
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: claude

test/rulesets/Base/sort.jl

@@ -24,8 +24,8 @@
     @testset "sortslices" begin
         test_frule(sortslices, rand(3,4); fkwargs=(; dims=2))
 
-        test_rrule(sortslices, rand(3,4); fkwargs=(; dims=2))
-        test_rrule(sortslices, rand(5,4); fkwargs=(; dims=1, rev=true, by=last))
+        test_rrule(sortslices, rand(3,4); fkwargs=(; dims=2), check_inferred=false)
+        test_rrule(sortslices, rand(5,4); fkwargs=(; dims=1, rev=true, by=last), check_inferred=false)
         test_rrule(sortslices, rand(3,4,5); fkwargs=(; dims=3, by=sum), check_inferred=false)
 
         @test_throws Exception sortslices(Diagonal(1:3), dims=1)