nb-flip-card not flipping back in safari / iOS

### Issue type

**I'm submitting a ...** (check one with "x")

* [ x] bug report
* [ ] feature request

### Issue description

**Current behavior:**
In iOS a flipcard is not flipping back from the reverse because the button is being covered by an overlaying div

**Expected behavior:**
Should flip back

**Steps to reproduce:**
To fix I added the following:
```
nb-flip-card.flipped {
.flipcard-body {
transform-style: flat;
}
}
```

### Other information:

**npm, node, OS, Browser**

node version 18.16.0
npm version 9.5.1
iOS 16 safari

**Angular, Nebular**

nebular version 11
Angular 15