[Minor] Add tests for temporal cast error paths

[alamb]

Which issue does this PR close?

N/A

Rationale for this change

While reviewing #2251 I noticed that the tests for string -> time/timestamp/date did not have coverage of the error paths (aka non safe casting)

Also, I want to refactor this code a little bit and before I did so I want to make sure the test coverage was good.

What changes are included in this PR?

Add test coverage

Are there any user-facing changes?

No

[alamb]

cc @stuartcarnie and @avantgardnerio

[ursabot]

Benchmark runs are scheduled for baseline = ad65e88 and contender = 6bb4b5e. 6bb4b5e is a master commit associated with this PR. Results will be available as each benchmark for each run completes.
Conbench compare runs links:
[Skipped ⚠️ Benchmarking of arrow-rs-commits is not supported on ec2-t3-xlarge-us-east-2] ec2-t3-xlarge-us-east-2
[Skipped ⚠️ Benchmarking of arrow-rs-commits is not supported on test-mac-arm] test-mac-arm
[Skipped ⚠️ Benchmarking of arrow-rs-commits is not supported on ursa-i9-9960x] ursa-i9-9960x
[Skipped ⚠️ Benchmarking of arrow-rs-commits is not supported on ursa-thinkcentre-m75q] ursa-thinkcentre-m75q
Buildkite builds:
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