build: remove crdb-protobuf-client node_modules with ui-maintainer-clean

[sjbarag]

Since version 33 [1], dev ui clean --all removes the
pkg/ui/workspaces/db-console/src/js/node_modules tree. Remove that tree
with make ui-maintainer-clean to keep parity between the two build
systems.

[1] 2e9e7a5 (dev: bump to version 33, 2022-05-27)

Release note: None

[cockroach-teamcity]

This change is 

[maryliag]

🚀

Reviewable status: complete! 1 of 0 LGTMs obtained

[sjbarag]

bors r=maryliag,rickystewart

[craig]

Build succeeded:

• GitHub CI (Cockroach)

[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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error creating merge commit from e9ac4e6 to blathers/backport-release-22.1-82740: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

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

Backport to branch 22.1.x failed. See errors above.

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