Update ordering tests

Author: YingboMa

test/order.jl

@@ -27,7 +27,7 @@ end
 @test istotal(b*a, a)
 @test istotal(a, b*a)
 @test !(b*a <ₑ b+a)
-@test Term(^, [1,-1]) <ₑ a
+@test a <ₑ Term(^, [1,-1])
 @test istotal(a, Term(^, [1,-1]))
 
 @testset "operator order" begin
@@ -57,8 +57,7 @@ end
 @testset "callable variable order" begin
     @syms z() ρ()
 
-    @test -1z() <ₑ ρ()
-    @test !(ρ() <ₑ -1z())
+    @test istotal(ρ(), -1z())
 
     @syms a(t) b(t) t
     @test a(t) <ₑ b(t)
@@ -73,7 +72,7 @@ end
     @syms x y
 
     @test x <ₑ (3 + x) && !((3 + x) <ₑ x)
-    @test x^2 <ₑ y && !(y <ₑ x^2)
+    @test istotal(y, x^2)
 
     # a nice consequence
     @test simplify(x/(x+3) + 3/(x+3)) == 1