simplify error make

[WindSoilder]

Description

Fixes: #5878

The simplest fix is just make error_make always returns Result::Err.

Breaking changes

I found that error_make is supporting pipeline input, which makes harder to adjust $env.LAST_STATUS_CODE to 1, to achieve this, we need to consider output result from table command, or make changes in eval_block.

More importantly, it's hard to make a decision if we get the following output value:

1. Value::Error(..)
2. [Value::Int(..), Value::Error(..), Value::Int(..)]
3. [Value::Error(..), Value::Error(..)]

Should nu think the result is success or not?

So I remove pipeline input support for error_make, and make error_struct from optional to required.

Tests

Make sure you've done the following:

• Add tests that cover your changes, either in the command examples, the crate/tests folder, or in the /tests folder.
• Try to think about corner cases and various ways how your changes could break. Cover them with tests.
• If adding tests is not possible, please document in the PR body a minimal example with steps on how to reproduce so one can verify your change works.

Make sure you've run and fixed any issues with these commands:

• cargo fmt --all -- --check to check standard code formatting (cargo fmt --all applies these changes)
• cargo clippy --workspace --features=extra -- -D warnings -D clippy::unwrap_used -A clippy::needless_collect to check that you're using the standard code style
• cargo test --workspace --features=extra to check that all the tests pass

[fdncred]

I've looked at this several times and I'm worried about how much code has been removed. This may be the perfect change, or maybe not. I'm not sure yet.

[WindSoilder]

Thanks for your feedback, I understand your concern, but I think it's fine, as long as error make doesn't pipeline input

[fdncred]

We can always revert if we need to. Thanks.