juju falsely claims that tools-metadata-url has ben supplied

[Aaron Bentley]

My environment does not contain a tools-metadata-url line, but juju claims:

The attribute "tools-url" should be removed from your configuration.
WARNING Config attribute "tools-url" (https://swift.canonistack.canonical.com/v1/AUTH_526ad877f3e3464589dc1145dfeaac60/juju-dist/testing/tools) is deprecated and will be ignored since
the new tools URL attribute "tools-metadata-url" has also been used.
The attribute "tools-url" should be removed from your configuration.

Since I have no tools-metadata-url entry in my configuration, removing "tools-url" would render my configuration unusable-- possibly permanently, if I don't have a record of tools-url's correct value.