Use ENV var to define default_comments_limit

[takahashim]

🎩 What? Why?

Rails.application.config.default_comments_limitを環境変数 DECIDIM_COMMENTS_LIMIT で上書きできるようにします。

📌 Related Issues

• Related to Feature/update decidim v0.23.5 codeforjapan/decidim-cfj#223

📋 Subtasks

• Add documentation regarding the feature

（どこかに書いておいた方が良さそう？）

[takahashim]

ちなみにこれで送信しているGraphQLのクエリは↓こんな感じのようです…（これでもjqで整形済みなんですが、queryの値の文字列が大変長いので思い切りはみ出てます）。

{
  "operationName": "GetComments",
  "variables": {
    "commentableId": "8",
    "commentableType": "Decidim::Debates::Debate",
    "orderBy": "older",
    "singleCommentId": null,
    "locale": "ja",
    "toggleTranslations": false,
    "limit": 5
  },
  "query": "query GetComments($commentableId: String!, $commentableType: String!, $orderBy: String, $singleCommentId: String, $locale: String!, $toggleTranslations: Boolean!, $limit: Int) {\n  session {\n    user {\n      name\n      nickname\n      avatarUrl\n      organizationName\n      __typename\n    }\n    ...AddCommentFormSession\n    __typename\n  }\n  commentable(id: $commentableId, type: $commentableType, locale: $locale, toggleTranslations: $toggleTranslations) {\n    acceptsNewComments\n    userAllowedToComment\n    commentsHaveAlignment\n    commentsHaveVotes\n    totalCommentsCount\n    comments(orderBy: $orderBy, singleCommentId: $singleCommentId, limit: $limit) {\n      id\n      ...CommentThread\n      __typename\n    }\n    ...AddCommentFormCommentable\n    __typename\n  }\n}\n\nfragment AddCommentFormSession on Session {\n  verifiedUserGroups {\n    id\n    name\n    __typename\n  }\n  __typename\n}\n\nfragment CommentThread on Comment {\n  hasComments\n  ...Comment\n  __typename\n}\n\nfragment Comment on Comment {\n  ...CommentData\n  comments {\n    ...CommentData\n    comments {\n      ...CommentData\n      comments {\n        ...CommentData\n        __typename\n      }\n      __typename\n    }\n    __typename\n  }\n  __typename\n}\n\nfragment CommentData on Comment {\n  id\n  sgid\n  type\n  body\n  formattedBody\n  createdAt\n  formattedCreatedAt\n  author {\n    name\n    nickname\n    avatarUrl\n    profilePath\n    deleted\n    badge\n    __typename\n  }\n  hasComments\n  acceptsNewComments\n  userAllowedToComment\n  alignment\n  alreadyReported\n  ...UpVoteButton\n  ...DownVoteButton\n  __typename\n}\n\nfragment UpVoteButton on Comment {\n  id\n  upVotes\n  upVoted\n  downVoted\n  __typename\n}\n\nfragment DownVoteButton on Comment {\n  id\n  downVotes\n  downVoted\n  upVoted\n  __typename\n}\n\nfragment AddCommentFormCommentable on Commentable {\n  id\n  type\n  __typename\n}\n"
}