few components with rspec3 syntax

spec/components/validators/username_setting_validator_spec.rb

@@ -5,17 +5,17 @@ describe UsernameSettingValidator do
     subject(:validator) { described_class.new }
 
     it "returns true for blank values" do
-      validator.valid_value?('').should == true
-      validator.valid_value?(nil).should == true
+      expect(validator.valid_value?('')).to eq(true)
+      expect(validator.valid_value?(nil)).to eq(true)
     end
 
     it "returns true if value matches an existing user's username" do
       Fabricate(:user, username: 'vader')
-      validator.valid_value?('vader').should == true
+      expect(validator.valid_value?('vader')).to eq(true)
     end
 
     it "returns false if value does not match a user's username" do
-      validator.valid_value?('no way').should == false
+      expect(validator.valid_value?('no way')).to eq(false)
     end
   end
 end