HTTP Error 500: Internal Server Error when calling get_audit_log with "after" variable

api.orgs.get_audit_log(ORG, per_page=10, page=2, after="2021-09-27T15:05:06+01:00")
// Here I'm using time format as per GHAPI rest docs. ghapi python docs suggest 2021-09-27 should work. Tried
// this and also timestamps, but all gave internal error.

If i remove the "after" variable, the call works fine.

I believe the problem is that the "after" variable is in [Link header format](api.orgs.get_audit_log(ORG, per_page=10, page=2, after="2021-09-27T15:05:06+01:00")) and perhaps this doesn't get autogenerated correctly.

Link: ; rel="next",

The value between after= and & does not completely URL + base64 decode to an obvious time format.

```
Signature:
api.orgs.get_audit_log(
org,
phrase=None,
include=None,
after=None,
before=None,
order=None,
per_page=None,
page=None,
)
Type: _GhVerb
String form:
orgs.get_audit_log(org, phrase=None, include=None, after=None, before=None, order=None, per_page=None, page=None)
https://docs.github.com/rest/reference/orgs#get-audit-log
File: /opt/conda/lib/python3.9/site-packages/ghapi/core.py
```

I would expect any values in the signature to specify the time format required, possibly add an example to the docs, and the error should be something less severe than a 500 internal error.

Beginne in /opt/conda/lib/python3.9/site-packages/ghapi/core.py und vergleiche, wie get_audit_log die Anfrage mit und ohne das Argument after erstellt. Prüfe die Dokumentation der GitHub audit-log API und reproduziere den bereitgestellten Aufruf unter Verwendung der dokumentierten Datums- und Zeitstempelformate; abgeschlossen ist die Aufgabe, wenn das unterstützte Format korrekt verarbeitet wird oder der ungültige Wert einen eindeutigen Fehler erzeugt und das erwartete Format dokumentiert ist.

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