sql/export: skip columns with Bit(0) type in parquet test

[aerfrei]

We were seeing failures on this randomized test when these columns were generated. The testutils parquet decoder can't handle this type (added in #132944) so these fail, but it doesn't represent a real issue.

This fix skips these the randomly generated test cases that include this column type.

Fixes: #154011
Epic: none
Release note: None

[cockroach-teamcity]

This change is 

[aerfrei]

Two random seeds that were helpful in verifying this off of master:
1802813790182486420 is a test failing with Bit(0)
4107181287183127133 is a seed with a column with non length 0 bit array that is not skipped.

[aerfrei]

bors r=KeithCh,asg0451

[craig]

Build succeeded:

• check_generated_code
• unit_tests
• linux_amd64_build
• linux_amd64_fips_build
• local_roachtest
• local_roachtest_fips
• examples_orms
• acceptance
• lint
• docker_image_amd64

[aerfrei]

blathers backport all

[blathers-crl]

Encountered an error creating backports. Some common things that can go wrong:

1. The backport branch might have already existed.
2. There was a merge conflict.
3. The backport branch contained merge commits.

You might need to create your backport manually using the backport tool.

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unexpected status code: 404 Not Found

Backport to branch all failed. See errors above.

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[aerfrei]

blathers backport-all

[blathers-crl]

Encountered an error creating backports. Some common things that can go wrong:

1. The backport branch might have already existed.
2. There was a merge conflict.
3. The backport branch contained merge commits.

You might need to create your backport manually using the backport tool.

---

error creating merge commit from 5c8981c to blathers/backport-release-24.3-160093: POST https://api.github.com/repos/aerfrei/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch release-24.3 failed. See errors above.

---

error creating merge commit from 5c8981c to blathers/backport-release-25.2-160093: POST https://api.github.com/repos/aerfrei/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch release-25.2 failed. See errors above.

---

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is dev-inf.}