Compare NULL types

[melgenek]

Which issue does this PR close?

Closes #4335.

Rationale for this change

These queries should produce a value instead of an error

❯ select null and null;
❯ select null or null;

What changes are included in this PR?

Null comparison coercion and tests.

I made the null logical comparison produce booleans. This is the Postgres does it, and DataFusion seems to be compatible with Postgres.

Are these changes tested?

Sqllogictests and unit tests

Are there any user-facing changes?

null and null and null or null would produce Boolean null value instead of an error.

[jackwener]

LGTM. Thanks @melgenek
cc @liukun4515

[alamb]

Love it -- thank you @melgenek

I double checked postgres

postgres=# select pg_typeof(null and null);
 pg_typeof
-----------
 boolean
(1 row)

[alamb]

👍

[ursabot]

Benchmark runs are scheduled for baseline = e41c4df and contender = 7d2d51b. 7d2d51b 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

[melgenek]

@alamb

I double checked postgres

The sqllogictest contains the same test as you performed manually https://github.com/melgenek/arrow-datafusion/blob/f1087f5c042ea093c6fd4d700dcecd8d2da6bf4a/datafusion/core/tests/sqllogictests/test_files/pg_compat/pg_compat_type_coercion.slt#L111-L115. It is just not visible in the git diff, because I added it in another pr