* Correctly rename stack files during a rename
This fixespulumi/pulumi#4463, by renaming a stack's configuration
file based on its stack-part, and ignoring the owner-part. Our
workspace system doesn't recognize configuration files with fully
qualified names. That, by the way, causes problems if we have
multiple stacks in different organizations that share a stack-part.
The fix here is simple: propagate the new StackReference from the
Rename operation and rely on the backend's normalization to a
simple name, and then use that the same way we are using a
StackReference to determine the path for the origin stack.
An alternative fix is to recognize fully qualified config files,
however, there's a fair bit of cleanup we will be doing as part of
https://github.com/pulumi/pulumi/issues/2522 and
https://github.com/pulumi/pulumi/issues/4605, so figured it is best
to make this work the way the system expects first, and revisit it
as part of those overall workstreams. I also suspect we may want to
consider changing the default behavior here as part of
https://github.com/pulumi/pulumi/issues/5731.
Tests TBD; need some advice on how best to test this since it
only happens with our HTTP state backend -- all integration tests
appear to use the local filestate backend at the moment.
* Add a changelog entry for bug fix
* Add some stack rename tests
* Fix a typo
* Address CR feedback
* Make some logic clearer
Use "parsedName" instead of "qn", add a comment explaining why
we're doing this, and also explicitly ignore the error rather
than implicitly doing so with _.