DNS Hosting: Update content on Moving to .gov

[montecristo99]

Issue description

We need to update the existing content to inform users that we now offer DNS hosting.

Acceptance criteria

• Rename existing section Find DNS hosting services to Set up DNS hosting services.
• Rewrite the blurb in this section to explain that users can either find their own hosting services or use the services we provide. Add a short value prop here (e.g. easy, convenient), then link to the new stand-alone page that explains more about DNS hosting. Also link to the step-by-step setup instructions, if those become their own page in the help section. Google doc for this content is here.
• Share content with product and DNS hosting pod.
• Create an implementation issue for this work and tag Product so it can be prioritized

Additional context

For clarity, this issue to write these updates in Google Docs and coordinate with the team. It's not to actually ship these updates to get.gov! That'll happen in ~May/June or so.

Links to other issues

🔄 #495

[h-m-f-t]

Added "create an implementation issue" to the A/Cs!

[montecristo99]

Content is here under the section "Find DNS hosting services."

[h-m-f-t]

I shared some comments in Slack and in the doc! Putting this back in In review.