feat: add mastodon chart

.gitlab-ci.yml

mastodon/Chart.yaml

mastodon/pipeline.yml

mastodon/templates/_helpers.tpl

mastodon/templates/deployment-sidekiq.yaml

mastodon/templates/deployment-streaming.yaml

mastodon/templates/deployment-web.yaml

mastodon/templates/ingress.yaml

mastodon/templates/pod-tootctl.yaml

mastodon/templates/secret.yaml

mastodon/templates/service-streaming.yaml

mastodon/templates/service-web.yaml

mastodon/values.yaml