only test printing length on 1.6 (also relax length for bigfloats)

Author: oxinabox

test/rand_tangent.jl

@@ -87,12 +87,13 @@ using FiniteDifferences: rand_tangent
         @test x + (rand_tangent(x) + rand_tangent(x)) isa typeof(x)
     end
 
-    @testset "niceness of printing" begin
+    # Julia 1.6 changed to using Ryu printing algorithm and seems better at printing short
+    VERSION > v"1.6" && @testset "niceness of printing" begin
         for i in 1:50
             @test length(string(rand_tangent(1.0))) <= 6
             @test length(string(rand_tangent(1.0 + 1.0im))) <= 12
             @test length(string(rand_tangent(1f0))) <= 12
-            @test length(string(rand_tangent(big"1.0"))) <= 8
+            @test length(string(rand_tangent(big"1.0"))) <= 9
         end
     end
 end