Readme.md: Update EDK II CI build status badge and links

Readme.md: Update EDK II CI build status badge and links

https://bugzilla.tianocore.org/show_bug.cgi?id=2315

Update Readme.md with the status badges from the Azure
Pipelines, tianocore organization, edk2-ci project

    https://dev.azure.com/tianocore/edk2-ci/_build

* Windows VS2019 CI pipeline badges and results
* Ubuntu GCC5 CI pipeline badges and results

Cc: Sean Brogan <sean.brogan@microsoft.com>
Cc: Bret Barkelew <Bret.Barkelew@microsoft.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Andrew Fish <afish@apple.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Sean Brogan <sean.brogan@microsoft.com>