Add gitlab-ci

.gitlab-ci.yml

+stages:
+  - build
+  - test
+
+.nvm_env: &nvm_env
+  tags:
+    - redshift-js-rs
+  before_script:
+    - export NVM_DIR="$HOME/.nvm"
+    - . "$NVM_DIR/nvm.sh"
+    - export PATH="$HOME/.cargo/bin:$PATH"
+  
+build:
+  <<: *nvm_env
+  stage: build
+  script:
+    - npm install
+
+test:
+  <<: *nvm_env
+  stage: test
+  script:
+    - npm install
+    - npm test