Bump symfony/monolog-bundle from 2.12.1 to 3.2.0

Bumps [symfony/monolog-bundle](https://github.com/symfony/monolog-bundle) from 2.12.1 to 3.2.0.
- [Release notes](https://github.com/symfony/monolog-bundle/releases)
- [Changelog](https://github.com/symfony/monolog-bundle/blob/master/CHANGELOG.md)
- [Commits](symfony/monolog-bundle@v2.12.1...v3.2.0)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]

composer.json

@@ -26,7 +26,7 @@
         "doctrine/doctrine-bundle": "^1.6",
         "doctrine/doctrine-cache-bundle": "^1.2",
         "symfony/swiftmailer-bundle": "^2.3",
-        "symfony/monolog-bundle": "^2.8",
+        "symfony/monolog-bundle": "^3.2",
         "symfony/polyfill-apcu": "^1.0",
         "sensio/distribution-bundle": "^5.0",
         "sensio/framework-extra-bundle": "^3.0.2",