Bump core-js from 2.5.1 to 3.1.2 in /terminus-core (#902)

Bump core-js from 2.5.1 to 3.1.2 in /terminus-core

terminus-core/package.json

@@ -23,7 +23,7 @@
     "@types/winston": "^2.3.6",
     "axios": "^0.18.0",
     "bootstrap": "^4.1.3",
-    "core-js": "^2.4.1",
+    "core-js": "^3.1.2",
     "electron-updater": "^2.8.9",
     "ng2-dnd": "^5.0.2",
     "ngx-perfect-scrollbar": "^6.0.0",

terminus-core/yarn.lock

@@ -180,10 +180,10 @@ combined-stream@^1.0.6, combined-stream@~1.0.6:
   dependencies:
     delayed-stream "~1.0.0"
 
-core-js@^2.4.1:
-  version "2.5.1"
-  resolved "https://registry.yarnpkg.com/core-js/-/core-js-2.5.1.tgz#ae6874dc66937789b80754ff5428df66819ca50b"
-  integrity sha1-rmh03GaTd4m4B1T/VCjfZoGcpQs=
+core-js@^3.1.2:
+  version "3.1.2"
+  resolved "https://registry.yarnpkg.com/core-js/-/core-js-3.1.2.tgz#2549a2cfb3ca1a5d851c9f7838e8b282cef2f3ba"
+  integrity sha512-3poRGjbu56leCtZCZCzCgQ7GcKOflDFnjWIepaPFUsM0IXUBrne10sl3aa2Bkcz3+FjRdIxBe9dAMhIJmEnQNA==
 
 core-util-is@1.0.2, core-util-is@~1.0.0:
   version "1.0.2"