Migrate from Travis to GitLab CI.

.gitlab-ci.yml

+---
+test:
+  image: alpine:3.12
+  before_script:
+    - apk add --update docker bats
+  script:
+    - bats .

.travis.yml

----
-language: c
-dist: trusty
-sudo: false
-group: beta
-services:
-  - docker
-
-script:
-  - bats test.bats
-
-notifications:
-  email: false
-  on_failure: never

README.md

 # Docker runas test
 
-[![Build Status](https://travis-ci.org/adarnimrod/docker-runas-test.svg?branch=master)](https://travis-ci.org/adarnimrod/docker-runas-test)
+ [![pipeline status](https://git.shore.co.il/nimrod/docker-runas-test/badges/master/pipeline.svg)](https://git.shore.co.il/nimrod/docker-runas-test/-/commits/master) 
 
 > A test suite for the runas Docker entrypoint.
 See [here](https://www.shore.co.il/blog/docker_uid/) for more info.
@@ -25,4 +25,4 @@ This software is licensed under the MIT license (see `LICENSE.txt`).
 Nimrod Adar, [contact me](mailto:nimrod@shore.co.il) or visit my [website](
 https://www.shore.co.il/). Patches are welcome via [`git send-email`](
 http://git-scm.com/book/en/v2/Git-Commands-Email). The repository is located
-at: <https://www.shore.co.il/git/>.
+at: <https://git.shore.co.il/explore/>.

test.bats

-#!/usr/bin/env bats
-
 _test_root () {
     name="${1:-$BATS_TEST_DESCRIPTION}"
     tag="${2:-latest}"