Bump behat/behat from 3.0.15 to 3.12.0

Bumps [behat/behat](https://github.com/Behat/Behat) from 3.0.15 to 3.12.0.
- [Release notes](https://github.com/Behat/Behat/releases)
- [Changelog](https://github.com/Behat/Behat/blob/master/CHANGELOG.md)
- [Commits](Behat/Behat@v3.0.15...v3.12.0)

---
updated-dependencies:
- dependency-name: behat/behat
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

composer.json

@@ -1,7 +1,7 @@
 {
     "name": "opencats/opencats",
     "require-dev": {
-        "behat/behat": "~3.0.4",
+        "behat/behat": "~3.12.0",
         "phpunit/phpunit": "^7",
         "behat/mink": "^1.7",
         "behat/mink-extension": "dev-master",