Column creation and duplication DDL 2

[mathemancer]

Related to #2690

This PR is another step in moving column creation/duplication DDL operations to the database.

Technical details

• modifies the python layer to use the column creation functions created in Add SQL for column adding #2923
• adds a column_copy function at the SQL layer, uses it in python
• Removes a bunch of python layer tests that were made redundant by new SQL layer tests

TODO

There is still a 'bulk create' function for columns in the python layer:

db.columns.operations.create.bulk_create_mathesar_column

This function won't be replaced, but will be deleted entirely when moving the table splitting/merging/column moving logic to the DB. So, we've skipped it for now.

Checklist

• My pull request has a descriptive title (not a vague title like Update index.md).
• My pull request targets the develop branch of the repository
• My commit messages follow best practices.
• My code follows the established code style of the repository.
• I added tests for the changes I made (if applicable).
• I added or updated documentation (if applicable).
• I tried running the project locally and verified that there are no
  visible errors.

Developer Certificate of Origin

Developer Certificate of Origin

Developer Certificate of Origin
Version 1.1

Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
1 Letterman Drive
Suite D4700
San Francisco, CA, 94129

Everyone is permitted to copy and distribute verbatim copies of this
license document, but changing it is not allowed.


Developer's Certificate of Origin 1.1

By making a contribution to this project, I certify that:

(a) The contribution was created in whole or in part by me and I
    have the right to submit it under the open source license
    indicated in the file; or

(b) The contribution is based upon previous work that, to the best
    of my knowledge, is covered under an appropriate open source
    license and I have the right under that license to submit that
    work with modifications, whether created in whole or in part
    by me, under the same open source license (unless I am
    permitted to submit under a different license), as indicated
    in the file; or

(c) The contribution was provided directly to me by some other
    person who certified (a), (b) or (c) and I have not modified
    it.

(d) I understand and agree that this project and the contribution
    are public and that a record of the contribution (including all
    personal information I submit with it, including my sign-off) is
    maintained indefinitely and may be redistributed consistent with
    this project or the open source license(s) involved.

[mathemancer]

To the reviewer:

It's probable that we still need to remove more python layer tests, or rework some fixtures. I think we should leave the bulk of test refactoring till after the functionality is complete.

[dmos62]

I would have been happy with the SQL version, but I think it's smart to dumb-down non-critical code 👍.

[dmos62]

These comments are very useful.

[dmos62]

Finding these aliases useful.

[dmos62]

👍