Version mismatch: latest tag is 4.1 but control file shows version 4.0

[gclough]

Hi Team,

I noticed a version mismatch in the system_stats repository.

The latest released Git tag is: 4.1
However, inside the extension control file, the version is still mentioned as: 4.0
This may cause confusion during packaging or extension installation where the control file version is used by PostgreSQL.

Could you please confirm:

Whether the control file version should be updated to 4.1, or
If the tag is incorrect and should reflect 4.0 instead?
Thanks!

Same as #60 for v3.2 and #24 for v2.1. I test these versions in my CI pipeline, so having mismatches makes life more difficult.