Ensure service and env are strings

lib/datadog/core/configuration/settings.rb

@@ -156,9 +156,7 @@ def initialize(*_)
         # @default `DD_ENV` environment variable, otherwise `nil`
         # @return [String,nil]
         option :env do |o|
-          # DEV-2.0: Remove this conversion for symbol.
-          o.setter { |v| v.to_s if v }
-
+          o.type :string, nilable: true
           # NOTE: env also gets set as a side effect of tags. See the WORKAROUND note in #initialize for details.
           o.env Core::Environment::Ext::ENV_ENVIRONMENT
         end
@@ -404,8 +402,7 @@ def initialize(*_)
         # @default `DD_SERVICE` environment variable, otherwise the program name (e.g. `'ruby'`, `'rails'`, `'pry'`)
         # @return [String]
         option :service do |o|
-          # DEV-2.0: Remove this conversion for symbol.
-          o.setter { |v| v.to_s if v }
+          o.type :string, nilable: true
 
           # NOTE: service also gets set as a side effect of tags. See the WORKAROUND note in #initialize for details.
           o.env Core::Environment::Ext::ENV_SERVICE

spec/datadog/core/configuration/settings_spec.rb

@@ -227,14 +227,6 @@
       it { expect(settings.env).to eq(env) }
     end
 
-    context 'when given a symbol' do
-      let(:env) { :symbol }
-
-      before { set_env }
-
-      it { expect(settings.env).to eq('symbol') }
-    end
-
     context 'when given `nil`' do
       let(:env) { nil }
 
@@ -839,14 +831,6 @@
       it { expect(settings.service).to eq(service) }
     end
 
-    context 'when given a symbol' do
-      let(:service) { :symbol }
-
-      before { set_service }
-
-      it { expect(settings.service).to eq('symbol') }
-    end
-
     context 'when given `nil`' do
       let(:service) { nil }