Please add layer for ap-south-1

Please add layer for ap-south-1.

Start by comparing the repository's existing Lambda layer definitions and build or release entry points for other regions, then determine how ap-south-1 should be represented. Done means the requested ap-south-1 layer is built and published consistently with the existing layers, with any available verification completed.

索引モデルが issue の本文から書いたものです。