[R] Implement dplyr::across() inside mutate()

[asfimport]

It's not a generic, but because it seems only to be called inside of functions like mutate(), we can insert our own version of it into the NSE data mask

Reporter: Neal Richardson / @nealrichardson
Assignee: Nicola Crane / @thisisnic

Related issues:

• [R] Implement dplyr::across() inside summarise() (blocks)
• [R] Implement dplyr::across() inside filter() (blocks)
• [R] Implement .names argument inside across() (blocks)
• [R] Implement dplyr::across() inside group_by() (relates to)
• [R] Implement use of where() inside `across() (relates to)
• [R] Implement dplyr::across() inside arrange() (relates to)
• [R] Implement dplyr::across() inside group_by() (relates to)
• [R] Implement dplyr::across() inside distinct() (is related to)

PRs and other links:

• GitHub Pull Request #13786
• GitHub Pull Request #14092

_{Note: This issue was originally created as ARROW-11699. Please see the migration documentation for further details.}

[asfimport]

Nicola Crane / @thisisnic:
This is something that there has been user interest in on Twitter: https://twitter.com/dseverski/status/1542237072798400514

[asfimport]

Nicola Crane / @thisisnic:
Issue resolved by pull request 13786
#13786