GH-33779: [R] Nightly builds (R 3.5 and 3.6) failing due to field refs test

[thisisnic]

This PR fixes a test which is failing on R versions < 4.0 due to the use of the function data.frame() which had a change in default parameter value for stringsAsFactors (from TRUE to FALSE) in 4.0, and so is behaving differently in these versions.

I've just swapped out the use of data.frame() for tibble::tibble() , which we use more prevalently in our tests, and has no such issues on earlier R version.

• Closes: [R] Nightly builds (R 3.5 and 3.6) failing due to field refs test #33779

[thisisnic]

@github-actions crossbow submit test-r-versions

[github-actions]

• Closes: [R] Nightly builds (R 3.5 and 3.6) failing due to field refs test #33779

[github-actions]

Revision: 13bcdda

Submitted crossbow builds: ursacomputing/crossbow @ actions-08f09d7ae3

Task	Status
test-r-versions

[paleolimbot]

stringsAsFactors = TRUE strikes again!

Thank you!

[ursabot]

Benchmark runs are scheduled for baseline = 4c698fb and contender = e920474. e920474 is a master commit associated with this PR. Results will be available as each benchmark for each run completes.
Conbench compare runs links:
[Finished ⬇️0.0% ⬆️0.0%] ec2-t3-xlarge-us-east-2
[Failed ⬇️1.41% ⬆️0.0%] test-mac-arm
[Failed] ursa-i9-9960x
[Finished ⬇️0.28% ⬆️0.0%] ursa-thinkcentre-m75q
Buildkite builds:
[Finished] e920474d ec2-t3-xlarge-us-east-2
[Finished] e920474d test-mac-arm
[Failed] e920474d ursa-i9-9960x
[Finished] e920474d ursa-thinkcentre-m75q
[Finished] 4c698fb3 ec2-t3-xlarge-us-east-2
[Failed] 4c698fb3 test-mac-arm
[Finished] 4c698fb3 ursa-i9-9960x
[Finished] 4c698fb3 ursa-thinkcentre-m75q
Supported benchmarks:
ec2-t3-xlarge-us-east-2: Supported benchmark langs: Python, R. Runs only benchmarks with cloud = True
test-mac-arm: Supported benchmark langs: C++, Python, R
ursa-i9-9960x: Supported benchmark langs: Python, R, JavaScript
ursa-thinkcentre-m75q: Supported benchmark langs: C++, Java

[ursabot]

['Python', 'R'] benchmarks have high level of regressions.
test-mac-arm