removing placeholder in meta

meta/main.yml

-# placeholder
\ No newline at end of file
+galaxy_info:
+  role_name: role-docker-installation
+  author: Jessica Hofmann
+  description: An ansible role to install docker and docker-compose. (see README.md for further information)
+
+  license: license (MIT)
+
+  min_ansible_version: 2.14.5
+
+  platforms:
+    - name: Debian
+      version:
+        - 11
+        - 12
+
+  galaxy_tags: []
+
+dependencies: []