chore: remove drone config

.drone.yml

@@ -1,59 +0,0 @@
-kind: pipeline
-name: testing
-
-trigger:
-  branch:
-    include:
-      - main
-  event:
-    include:
-      - push
-      - pull_request
-
-steps:
-  - name: build
-    image: vikunja/golang-build:latest
-    pull: true
-    environment:
-      GOPROXY: 'https://goproxy.kolaente.de'
-    commands:
-      - go build .
-
-  - name: test
-    image: vikunja/golang-build:latest
-    pull: true
-    environment:
-      GOPROXY: 'https://goproxy.kolaente.de'
-      BACKUP_FOLDER: ./backups
-    commands:
-      - go test
-
----
-kind: pipeline
-name: docker
-
-depends_on:
-  - testing
-
-trigger:
-  ref:
-    - refs/heads/main
-    - "refs/tags/**"
-
-steps:
-  - name: fetch-tags
-    image: docker:git
-    commands:
-      - git fetch --tags
-
-  - name: docker-prod
-    image: plugins/docker:linux-amd64
-    pull: true
-    settings:
-      username:
-        from_secret: docker_username
-      password:
-        from_secret: docker_password
-      repo: kolaente/db-backup
-      tags: latest
-    depends_on: [ fetch-tags ]