Also remove PathPerfTests.swift from the Linux test manifest.
Also remove PathPerfTests.swift from the Linux test manifest.

apple/swift-package-manager,haskellswift/swift-package-manager,sschiau/swift-package-manager,JGiola/swift-package-manager,abertelrud/swift-package-manager,mxcl/swift-package-manager,apple/swift-package-manager,mxcl/swift-package-manager,sschiau/swift-package-manager,JGiola/swift-package-manager,abertelrud/swift-package-manager,vmanot/swift-package-manager,JGiola/swift-package-manager,apple/swift-package-manager,sschiau/swift-package-manager,vmanot/swift-package-manager,abertelrud/swift-package-manager,apple/swift-package-manager,haskellswift/swift-package-manager,sschiau/swift-package-manager,JGiola/swift-package-manager,haskellswift/swift-package-manager,haskellswift/swift-package-manager,abertelrud/swift-package-manager,abertelrud/swift-package-manager,sschiau/swift-package-manager,vmanot/swift-package-manager,vmanot/swift-package-manager,apple/swift-package-manager,mxcl/swift-package-manager,vmanot/swift-package-manager,mxcl/swift-package-manager,JGiola/swift-package-manager