Updated CI pipeline

* Added `deploy` stage, pushing the current master build to NuGet

.gitlab-ci.yml

@@ -4,7 +4,7 @@ stages:
   - build
   - test
   - pack
-#  - deploy
+  - deploy
 #  - release
 
 before_script:
@@ -23,7 +23,7 @@ build:
 test:
   stage: test
   script: dotnet test TerminalTests
-  
+
 pack:
   stage: pack
   script: dotnet pack ./Terminal/
@@ -31,3 +31,10 @@ pack:
     paths:
       - ./Terminal/bin/Debug/netstandard2.0/*.dll
       - ./Terminal/bin/Debug/*.nupkg
+
+deploy:nuget:
+  stage: deploy
+  script: dotnet nuget push ./Terminal/bin/Debug/*.nupkg -k $NUGET_API_KEY
+  only:
+    refs:
+      - master