Remove LocalSpannerIO and uses Beam's SpannerIO for Spanner Templates#1429

Abacn wants to merge 2 commits intoGoogleCloudPlatform:mainGoogleCloudPlatform/DataflowTemplates:mainfrom

Abacn:removelocalspannerioAbacn/DataflowTemplates:removelocalspannerioCopy head branch name to clipboard