Do not add pretty_errors as a requirement (#45)

pretty_errors is only a debug requirement https://github.com/Lightning-AI/torchmetrics/blob/bfcd4b0e5bfa1256ef9c142956a86df57542a668/requirements/debug.txt
installing this package will change the traceback output of python as soon as torchmetrics is imported. It was so difficult to find out what was changing tracebacks in my script.

recipe/meta.yaml

@@ -11,15 +11,14 @@ source:
 
 build:
   noarch: python
-  number: 0
+  number: 1
   script: {{ PYTHON }} -m pip install . -vv
 
 requirements:
   host:
     - pip
     - python >=3.8
   run:
-    - pretty_errors ==1.2.25
     - numpy >1.20.0
     - packaging >17.1
     - setuptools