Correct hypot examples

Author: nickrobinson251

src/rules.jl

@@ -26,7 +26,7 @@ true
 
 julia> Δx, Δy = rand(2);
 
-julia> dh(Δx, Δy) == ((y / h) * Δx + (x / h) * Δy)
+julia> dh(Δx, Δy) == ((x / h) * Δx + (y / h) * Δy)
 true
 
 julia> h, (dx, dy) = rrule(hypot, x, y);
@@ -39,10 +39,10 @@ true
 
 julia> Δh = rand();
 
-julia> dx(Δh) == (y / h) * Δh
+julia> dx(Δh) == (x / h) * Δh
 true
 
-julia> dy(Δh) == (x / h) * Δh
+julia> dy(Δh) == (y / h) * Δh
 true
 ```
 
@@ -340,10 +340,10 @@ julia> hypotxy, (dx, dy) = rrule(hypot, x, y);
 julia> hypotxy == hypot(x, y)
 true
 
-julia> dx(1) == (y / hypot(x, y))
+julia> dx(1) == (x / hypot(x, y))
 true
 
-julia> dy(1) == (x / hypot(x, y))
+julia> dy(1) == (y / hypot(x, y))
 true
 ```