BaseTools: Update WindowsVsToolChain plugin

This patch updates edk2-pytool-library dependency to v0.14.0, which has
an interface change to FindWithVsWhere. The BaseTools plugin uses this
function, so it is being updated to account for the interface change.

Cc: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Yuwei Chen <yuwei.chen@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>

Signed-off-by: Joey Vagedes <joeyvagedes@microsoft.com>
Acked-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>

pip-requirements.txt

@@ -12,8 +12,8 @@
 # https://www.python.org/dev/peps/pep-0440/#version-specifiers
 ##
 
-edk2-pytool-library==0.12.1
-edk2-pytool-extensions~=0.20.0
+edk2-pytool-library==0.14.0
+edk2-pytool-extensions~=0.21.8
 edk2-basetools==0.1.39
 antlr4-python3-runtime==4.7.1
 lcov-cobertura==2.0.2