Bump core-js from 3.1.2 to 3.1.3 in /terminus-core (#965)
Bump core-js from 3.1.2 to 3.1.3 in /terminus-core (#965)

Bump core-js from 3.1.2 to 3.1.3 in /terminus-core
Eugeny/terminus,Eugeny/terminus,Eugeny/terminus,Eugeny/terminus,Eugeny/terminus,Eugeny/terminus