GitHubAuditData parser dropping logs

**Describe the bug**
I’ve identified the problem with the GitHubAuditData parser.

https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/GitHub/Parsers/GitHubAuditData.yaml

It uses a function called unixtime_milliseconds_todatetime() on the column “CreatedAt” which doesn’t always exist. This means for those rows it’s returning null and effectively filtering them out from the source.

It doesn't seem to be isolated or a logging issue. I work for an MSSP and can see the same discrepancy across all of our customers with the data source as well.

**To Reproduce**
Steps to reproduce the behavior:
1. Go to 'Functions' in Log Analytics
2. Click on 'Load code to editor' when hovered over GitHubAuditData
3. Scroll down to lines 4 and 22.
4. See issue described above. If you comment these out the returned results will increase significantly.

**Expected behavior**
Implement a fallback or remove this filter entirely. When I compared the existing default TimeGenerated column to the new extended column (where CreatedAt was populated) there was no difference.

**Screenshots**

**Desktop (please complete the following information):**
- OS: Windows
- Browser: Edge
- Version: 150.0.4078.48

**Smartphone (please complete the following information):**
N/A

**Additional context**
I'd be grateful if you could confirm when we can expect the fix to be pushed Sentinel side and what the remediation steps would be for us. Should it just be a case of updating the parser via the Content Hub or will there be some additional manual work required?