Check if Two Circles Intersect solution_09

This test is failing; It doesn't account for the fact that the circles are touching at one point.
```python
def test_circles_touching_at_one_point_intersect():
    c1 = Circle(0, 0, 5)
    c2 = Circle(10, 0, 5)
    assert do_circles_intersect(c1, c2) is True
```