Remove unused test for Redis cache store (#9102)

spec/initializers/active_support/cache/redis_cache_store_spec.rb

@@ -1,48 +0,0 @@
-require "rails_helper"
-
-RSpec.describe ActiveSupport::Cache::RedisCacheStore do
-  let(:redis_client) { ActiveSupport::Cache.lookup_store(:redis_cache_store).redis }
-  let(:cache_db) { described_class.new }
-  let(:key) { "monkey_patch_test" }
-
-  def value
-    cache_db.read(key, raw: true).to_i
-  end
-
-  def pttl
-    redis_client.pttl(key)
-  end
-
-  describe ".increment" do
-    before do
-      cache_db.delete(key)
-    end
-
-    it "increments value without expires_in" do
-      cache_db.increment(key)
-
-      expect(value).to eq(1)
-      expect(pttl).to eq(-1)
-
-      cache_db.increment(key)
-
-      expect(value).to eq(2)
-      expect(pttl).to eq(-1)
-    end
-
-    it "increments value with expires_in" do
-      cache_db.increment(key, 1, expires_in: 100.seconds)
-      first_pttl = pttl
-
-      expect(value).to eq(1)
-      expect(first_pttl > 0).to be_truthy
-      expect(first_pttl <= 100_000).to be_truthy
-
-      cache_db.increment(key, 1, expires_in: 200.seconds)
-      second_pttl = pttl
-
-      expect(value).to eq(2)
-      expect(second_pttl <= first_pttl).to be_truthy
-    end
-  end
-end