upgrade database_cleaner

Gemfile

@@ -176,7 +176,7 @@ group :development, :test do
   gem "annotate", "~> 3.1"
   gem "assert_difference", "~> 1.0" # Deprecated: Barely used, convert usage to something else.
   gem "awesome_print", "~> 1.6"
-  gem "database_cleaner", "~> 1.7"
+  gem "database_cleaner", "~> 2.0"
   gem "db-query-matchers", "~> 0.10"
   gem "rubocop", "1.22.1" # Hound supported versions: http://help.houndci.com/en/articles/2461415-supported-linters
   gem "rubocop-rails", "~> 2.8"

Gemfile.lock

@@ -200,7 +200,12 @@ GEM
     daemons (1.4.1)
     dalli (3.2.7)
       base64
-    database_cleaner (1.99.0)
+    database_cleaner (2.0.2)
+      database_cleaner-active_record (>= 2, < 3)
+    database_cleaner-active_record (2.1.0)
+      activerecord (>= 5.a)
+      database_cleaner-core (~> 2.0.0)
+    database_cleaner-core (2.0.1)
     date (3.3.4)
     db-query-matchers (0.12.0)
       activesupport (>= 4.0, < 7.2)
@@ -654,7 +659,7 @@ DEPENDENCIES
   closure_tree!
   daemons (~> 1.2)
   dalli (~> 3.2)
-  database_cleaner (~> 1.7)
+  database_cleaner (~> 2.0)
   db-query-matchers (~> 0.10)
   delayed_job_active_record (~> 4.1)
   descriptive_statistics (~> 2.5)