Add testing CI

This commit extends our CI definitions to add a testing phase to the pipeline.
The testing phase is intended to be comprised of separate stages per package
that has tests included. Currently this consists of the state and config
packages.

Signed-off-by: Ava Affine <ava@sunnypup.io>

.gitlab-ci.yml

@@ -2,6 +2,7 @@ image: golang:latest
 
 stages:
   - build
+  - test
 
 compile:
   stage: build
@@ -11,3 +12,13 @@ compile:
     paths:
       - bingobot
       - start.sh
+
+tests-state-pkg:
+  stage: test
+  script:
+    - go test ./internal/state
+
+tests-config-pkg:
+  stage: test
+  script:
+    - go test ./internal/config