Move common code used for testing code into datafusion/test_utils

[alamb]

Which issue does this PR close?

Closes #3960

Rationale for this change

I want to reuse this code

See more detail on #3960

What changes are included in this PR?

Consolidate code that is helpful for testing into a test_utils crate:

1. "fuzz_utils"
2. A data generator for access-log like data

Are there any user-facing changes?

No -- this just moves code around

[alamb]

I wonder if @xudong963 or @Ted-Jiang has a few minutes to review this too (I think it is fairly straightforward)

[xudong963]

LGTM

[ursabot]

Benchmark runs are scheduled for baseline = 6860ae4 and contender = 8792a01. 8792a01 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-datafusion-commits is not supported on ec2-t3-xlarge-us-east-2] ec2-t3-xlarge-us-east-2
[Skipped ⚠️ Benchmarking of arrow-datafusion-commits is not supported on test-mac-arm] test-mac-arm
[Skipped ⚠️ Benchmarking of arrow-datafusion-commits is not supported on ursa-i9-9960x] ursa-i9-9960x
[Skipped ⚠️ Benchmarking of arrow-datafusion-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

[alamb]

Thanks @xudong963 !