[R] bindings for sign()

[asfimport]

Following ARROW-12861

Reporter: Neal Richardson / @nealrichardson
Assignee: Neal Richardson / @nealrichardson

Related issues:

• [R] Bindings for sign() (is duplicated by)

PRs and other links:

• GitHub Pull Request #10735

_{Note: This issue was originally created as ARROW-13357. Please see the migration documentation for further details.}

[asfimport]

Neal Richardson / @nealrichardson:
Issue resolved by pull request 10735
#10735