The tag is present in Lintian version 2.104.234. That is the most recent version we know about.
The VCS-* field contains more spaces than expected or spaces at places where they were not expected. Where possible, escape valid spaces in URIs to avoid any ambiguity with respect to possible future additional optional fields.
This may be caused by incorrect use of the
Refer to Debian Policy Manual section 5.6.26 for details.