Add /APPCONTAINER linker flag to shared libraries in UWP builds. Bug: angleproject:4181 Change-Id: I6940d5605e85bcf923b201be0f0f2b1f61c30ed5 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1944463 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>