v3 to v4 messages should only be signaled once per session

[olivroy]

Thanks to #854, it is a little easier to know how to switch code from v3 to v4.

However, these messages can be a little overwhelming. As mentioned in #888 (comment)

I will wait for #851 to do this.

I will use cli to do this. https://rlang.r-lib.org/reference/abort.html#muffling-and-silencing-conditions

[mtennekes]

Thx! #851 is done, but not sure what the relation with the messaging is...

[Nowosad]

I am now trying a lot of old tmap3 code -- I am very impressed with the messages helping to convert the code from the old syntax to the new one. Great work @olivroy @mtennekes