swift

7ce649c1 - [Windows] Use a multiroot data file to test (corelibs-)foundation on Windows

[Windows] Use a multiroot data file to test (corelibs-)foundation on Windows We currently rebuild swift-syntax, swift-foundation-icu and swift-foundation twice: Once to test swift-foundation and once to test swift-corelibs-foundation. Using a unified build for both projects means that we only need to rebuild them once, saving ~5 minutes. (cherry picked from commit 61f833c04c6ef9521b59d9ba7749cb1d862c0ed2)