Use box linters

[radbasa]

Draft until box.linters is released on CRAN. box.linters@0.9.0 released

Closes #582

Description

• update rhino app template .lintr
• removed linter functions and unit tests

Definition of Done

• [ ] The change is thoroughly documented.
• [ ] The CI passes (R CMD check, linter, unit tests, spelling).
• [ ] Any generated files have been updated (e.g. .Rd files with roxygen2::roxygenise())

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 20.65%. Comparing base (82476b5) to head (60cda16).

:exclamation: Current head 60cda16 differs from pull request most recent head 0e9d8b7

Please upload reports for the commit 0e9d8b7 to get more accurate results.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #583 +/- ## =========================================== - Coverage 38.55% 20.65% -17.91% =========================================== Files 10 9 -1 Lines 594 460 -134 =========================================== - Hits 229 95 -134 Misses 365 365 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.