Scale isolated label ASW

[mumichae]

Isolated label ASW is not scaled, so that the expected output range would be between -1 and +1

https://github.com/theislab/scib/blob/98ee9a20260993ca5df960054dcc82ff8fd75b20/scib/metrics/isolated_labels.py#L237-L249

Solution: Add scaling option to metric

[codecov[bot]]

Codecov Report

Merging #371 (225adf6) into main (98ee9a2) will increase coverage by 0.05%. The diff coverage is 100.00%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #371 +/- ## ========================================== + Coverage 53.13% 53.18% +0.05% ========================================== Files 22 22 Lines 1850 1852 +2 ========================================== + Hits 983 985 +2 Misses 867 867 ``` | Flag | Coverage Δ | | |---|---|---| | unittests | `53.18% <100.00%> (+0.05%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=theislab#carryforward-flags-in-the-pull-request-comment) to find out more. | [Impacted Files](https://codecov.io/gh/theislab/scib/pull/371?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=theislab) | Coverage Δ | | |---|---|---| | [scib/metrics/isolated\_labels.py](https://codecov.io/gh/theislab/scib/pull/371?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=theislab#diff-c2NpYi9tZXRyaWNzL2lzb2xhdGVkX2xhYmVscy5weQ==) | `92.98% <100.00%> (+0.25%)` | :arrow_up: |

[LuckyMD]

We'll need a new release and then an open problems PR to pin to that release @danielStrobl