full_simplify involving square root without success

<div id="comment:0"></div>


```
sage: var('r')
r
sage: t = (sqrt(3) + 4/(sqrt(3) + I) + I)/r^(1/2)
sage: t.full_simplify()
(2*I*sqrt(3) + 6)/(sqrt(r)*(sqrt(3) + I))
```
Note that simplify by getting rid of the factor `r^(1/2)` it works::

```
sage: (t*r^(1/2)).full_simplify()
2*sqrt(3)
```


Component: **symbolics**

_Issue created by migration from https://trac.sagemath.org/ticket/19995_

