[MERGE #2247 @dilijev] Update release/1.2 version to 1.2.3.
[MERGE #2247 @dilijev] Update release/1.2 version to 1.2.3.

Merge pull request #2247 from dilijev:v123

mrkmarron/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,mrkmarron/ChakraCore,mrkmarron/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,mrkmarron/ChakraCore,mrkmarron/ChakraCore