There is "url://example.com" in your copyright file. This was most likely a remnant from the dh_make template.
Make sure you include the real location where you obtained the upstream sources (if any).
For more information please consult:
- Debian Policy Manual section 12.5
The tag is present in Lintian version
That is the most recent version we know about.
We use semantic versions.
The patch number is a commit step indicator relative to the
release tag in our Git
You can find the detection logic for this version at commit ffc17eb. For merge requests, please use the latest version in the Lintian check debian/copyright.