* Fix stack.yaml filtering when resolver file is in a subdirectory
`maybeCleanedSource` tries to include the resolver file into the cleaned
source, if a resolver is specified, but it was only working when the
file was in the root of the project, because all directories would be
filtered out.
* fixup! Fix stack.yaml filtering when resolver file is in a subdirectory
Fix calculating relPath for paths using subDir
* Add test case for local stack snapshot located in a subdirectory
Zhenya Vinogradov