[Fix #301] Set disabled by default for Rails/PluckId

Fixes #301.

This PR sets disabled by default for `Rails/PluckId`.
An array object does not support `ids` method, that only works for
an AR object. So, this PR defaults to prevent false alarms cause by it.

CHANGELOG.md

@@ -6,6 +6,10 @@
 
 * [#297](https://github.com/rubocop-hq/rubocop-rails/pull/297): Handle an upstream Ruby issue where the DidYouMean module is not available, which would break the `Rails/UnknownEnv` cop. ([@taylorthurlow][])
 
+### Changes
+
+* [#301](https://github.com/rubocop-hq/rubocop-rails/issues/301): Set disalbed by default for `Rails/PluckId`. ([@koic][])
+
 ## 2.7.0 (2020-07-21)
 
 ### New features

config/default.yml

@@ -417,7 +417,7 @@ Rails/Pluck:
 Rails/PluckId:
   Description: 'Use `ids` instead of `pluck(:id)` or `pluck(primary_key)`.'
   StyleGuide: 'https://rails.rubystyle.guide/#ids'
-  Enabled: 'pending'
+  Enabled: false
   Safe: false
   VersionAdded: '2.7'
 

docs/modules/ROOT/pages/cops_rails.adoc

@@ -2408,7 +2408,7 @@ Post.published.pluck(:title)
 |===
 | Enabled by default | Safe | Supports autocorrection | VersionAdded | VersionChanged
 
-| Pending
+| Disabled
 | No
 | Yes (Unsafe)
 | 2.7