Remove ambiguous array into_iter usage in tests.

See rust-lang/rust#66145. The removed checks aren't particularly useful and
might turn into build errors in the next rust edition.

Author: nical

src/angle.rs

@@ -348,5 +348,4 @@ fn sum() {
     let angles = [A::radians(1.0), A::radians(2.0), A::radians(3.0)];
     let sum = A::radians(6.0);
     assert_eq!(angles.iter().sum::<A>(), sum);
-    assert_eq!(angles.into_iter().sum::<A>(), sum);
 }

src/length.rs

@@ -406,7 +406,6 @@ mod tests {
         let lengths = [L::new(1.0), L::new(2.0), L::new(3.0)];
 
         assert_eq!(lengths.iter().sum::<L>(), L::new(6.0));
-        assert_eq!(lengths.into_iter().sum::<L>(), L::new(6.0));
     }
 
     #[test]

src/size.rs

@@ -805,7 +805,6 @@ mod size2d {
             ];
             let sum = Size2D::new(3.0, 6.0);
             assert_eq!(sizes.iter().sum::<Size2D<_>>(), sum);
-            assert_eq!(sizes.into_iter().sum::<Size2D<_>>(), sum);
         }
 
         #[test]
@@ -1695,7 +1694,6 @@ mod size3d {
             ];
             let sum = Size3D::new(3.0, 6.0, 9.0);
             assert_eq!(sizes.iter().sum::<Size3D<_>>(), sum);
-            assert_eq!(sizes.into_iter().sum::<Size3D<_>>(), sum);
         }
 
         #[test]

src/vector.rs

@@ -2207,7 +2207,6 @@ mod vector2d {
         ];
         let sum = Vector2DMm::new(9.0, 12.0);
         assert_eq!(vecs.iter().sum::<Vector2DMm<_>>(), sum);
-        assert_eq!(vecs.into_iter().sum::<Vector2DMm<_>>(), sum);
     }
 
     #[test]
@@ -2273,7 +2272,6 @@ mod vector3d {
         ];
         let sum = Vec3::new(12.0, 15.0, 18.0);
         assert_eq!(vecs.iter().sum::<Vec3>(), sum);
-        assert_eq!(vecs.into_iter().sum::<Vec3>(), sum);
     }
 
     #[test]