Remove invalid schema attr

[leandrocp]

On Ecto v3.8.0 I started getting the following error:

== Compilation error in file lib/my_app/accounts/user_identity.ex ==
** (ArgumentError) invalid option :null for field/3
    (ecto 3.8.0) lib/ecto/schema.ex:2214: Ecto.Schema.check_options!/3
    (ecto 3.8.0) lib/ecto/schema.ex:1911: Ecto.Schema.__field__/4
    (elixir 1.13.4) lib/enum.ex:937: Enum."-each/2-lists^foreach/1-0-"/2
    lib/my_app/accounts/user_identity.ex:8: (module)
    (elixir 1.13.4) lib/kernel/parallel_compiler.ex:346: anonymous fn/5 in Kernel.ParallelCompiler.spawn_workers/7

Which makes sense because null is not a valid attr (seems like it has never been), see https://github.com/elixir-ecto/ecto/blob/4fa2c26dc2064aa2963b96bddee662d18a63e7fd/lib/ecto/schema.ex#L491-L507

I just don't know why it started failing on Ecto v3.8.0 and not on previous versions, but either way seems like that null: false should be removed.

Tested on Elixir v1.13.0 and v1.13.4

[danschultzer]

Thanks! I've released v0.4.13 to resolve this. In ecto_sql 3.8.0 the options for fields are now validated. We still need the migration columns to have NOT NULL constraint set to ensure data integrity. I've separated the two options so they are dealt with appropriately, and this makes it trivial to add any options in the future if necessary.

Let me know if there's any issues with this release!

[leandrocp]

Thanks! I've released v0.4.13 to resolve this. In ecto_sql 3.8.0 the options for fields are now validated. We still need the migration columns to have NOT NULL constraint set to ensure data integrity. I've separated the two options so they are dealt with appropriately, and this makes it trivial to add any options in the future if necessary.

Let me know if there's any issues with this release!

Thanks! I didn't realize attrs were used by migrations too but it makes sense. I'll give it a try and let you know if something doesn't work as expected.