Add feature preview for container registry (#16424)

* Add new article with user account procedure

* Update reusables

* Add other prereq

* Add product variable

* Add a reminder reusable for getting started procedures

* Revise organization article

* Condense enabling articles into one

* Deets

* Delete old article

* wording tweak

* Minor tweak

* Add personal user account explanation

* Rework explanation

* Apply suggestions from code review

Co-authored-by: Kayla Ngan <kaylangan@github.com>

* Apply suggestions from code review

Co-authored-by: Lucas Costi <lucascosti@users.noreply.github.com>

* Apply suggestions from code review

Co-authored-by: Kayla Ngan <kaylangan@github.com>

* Update screenshot and remove other feature previews

* Create a reusable for accessing the feature preview

* ✂️ per @lucascosti's suggestion

* Update images

* Update article title

* Apply suggestions from code review

Co-authored-by: Lucas Costi <lucascosti@users.noreply.github.com>

* Apply suggestions from code review

Co-authored-by: Kayla Ngan <kaylangan@github.com>
Co-authored-by: Lucas Costi <lucascosti@users.noreply.github.com>

content/github/getting-started-with-github/exploring-early-access-releases-with-feature-preview.md

@@ -21,7 +21,6 @@ versions:
 
 You can see a list of features that are available in beta and a brief description for each feature. Each feature includes a link to give feedback.
 
-1. In the upper-right corner of any page, click your profile photo, then click **Feature preview**.
-  ![Feature preview button](/assets/images/help/settings/feature-preview-button.png)
+{% data reusables.feature-preview.feature-preview-setting  %}
 2. Optionally, to the right of a feature, click **Enable** or **Disable**.
   ![Enable button in feature preview](/assets/images/help/settings/enable-feature-button.png)