Add Google Analytics to the blog

[chalin]

• The blog is currently hosted on Medium, it would seem, at blog.envoyproxy.io. Can someone with right permissions enable Google Analytics 4 using the following ID, G-DXJEH1ZRXX?
• Related: Migrate to Google Analytics 4 (GA4) #273

/cc @phlax @mattklein123

[chalin]

/cc @nate-double-u @caniszczyk

[chalin]

@phlax @mattklein123 - until #281 gets implemented, could one of you add an / update the analytics ID used on Medium? (For the GA ID to use, see the opening comment..)

[chalin]

FYI, I was double checking that the Blog didn't have any analytics but found a legacy UA ID registered with it:

Apparently this is a Medium-wide UA ID.