Fix property access in production and turn on prod testing

[igorT]

Fixes #1371

[github-actions]

Performance Report for 38045f2

Scenario - materializing-lots: ☑️ Performance is stable

☑️ duration
phase no difference [-13ms to 135ms]
☑️ Phase [navigationStart] => [start-loading]
phase no difference [-4ms to 8ms]
⚠️ Phase [start-loading] => [pushed-payload]
phase estimated regression +80ms [44ms to 120ms] OR +1.75% [0.95% to 2.61%]
☑️ Phase [pushed-payload] => [end-loading]
phase no difference [-56ms to 24ms]
☑️ Phase [end-loading] => [Test End]
phase no difference [0ms to 2ms]

Scenario - materializing-small: ☑️ Performance is stable

☑️ duration
phase no difference [-6ms to 8ms]
☑️ Phase [navigationStart] => [start-loading]
phase no difference [-2ms to 7ms]
☑️ Phase [start-loading] => [pushed-payload]
phase no difference [-3ms to 0ms]
☑️ Phase [pushed-payload] => [end-loading]
phase no difference [-2ms to 1ms]
☑️ Phase [end-loading] => [Test End]
phase no difference [-1ms to 1ms]

Scenario - rendering: ☑️ Performance is stable

☑️ duration
phase no difference [-24ms to 21ms]
☑️ Phase [navigationStart] => [start-loading]
phase no difference [-8ms to 3ms]
☑️ Phase [start-loading] => [pushed-payload]
phase no difference [-4ms to 0ms]
☑️ Phase [pushed-payload] => [end-loading]
phase no difference [-1ms to 1ms]
☑️ Phase [end-loading] => [Test End]
phase no difference [-15ms to 22ms]

[hjdivad]

LGTM, only real complaint is let's update the comment in the proxy as the code is a little tricky and it depends on particular details of Ember.get

[hjdivad]

LGTM please combine the commits before merging so we have clean commit history