Update copy from "template preview" to "show template"

[annezazu]

Digging into the template preview feature during a recent hallway hangout, we discussed the language around "template preview" being confusing in that one would expect this to bring you to a template preview. I see this was decided here. Can we return to the original proposed language with "show template"?

[jasmussen]

CC: @jameskoster

[jameskoster]

The concern with "Show template" was that it might be interpreted as a setting for the post/page, and consequently affect the frontend. That was purely an assumption though, so no harm trying it imo.

[carolinan]

It took me some time to figure out what part of the interface you meant.

I think it might be easier if the text changed depending on the state, so that when the template is visible, the text could say "Hide template"

[juanfra]

Closing as completed in #57802