Remove duplicates in PathsAndMissingDepsRelativeToModuleSourceDir

This change prevents duplicate paths from being returned when resolving
filepath, glob and ":name{.tag}" syntax to android.Paths. Once all
existing modules are cleaned up to remove duplicates in the source
files, the duplicates removal can be converted into an error so that
passing duplicate source files in the module definition is restricted.

Test: patch to git_main, inspect ninja commands
Bug: 326674683
Change-Id: I38a4ce9238da25cd67968f6bc8058bc9facc4551