fix(mssql): return aggregated error instead of last error

[lohart13]

Pull Request Checklist

• Have you added new tests to prevent regressions?
• If a documentation update is necessary, have you opened a PR to the documentation repository?
• Did you update the typescript typings accordingly (if applicable)?
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Description Of Change

Return aggregated for MSSQL when the error object as an error.errors length greater than 0.

[WikiRik]

Looks good in general. Would it be possible to add a test that checks for the other errors as well to make sure it's not giving back random messages/errors?

[lohart13]

@WikiRik I've added some more tests now.
LMK if you have any others error tests in mind.

All other errors with either return an AggregateError or DatabaseError

[WikiRik]

There's a few instances where you can better use backticks for strings so you have less instances of escaping single quotes, but I want to look for a eslint rule to fix that so it's fine here

@ephys might have some suggestions for using decorators in the tests, but we haven't made a clear policy on that yet (or given some guidelines in CONTRIBUTING docs)

[WikiRik]

I'll merge this anyway, but @ephys feel free to still comment on usages of decorators in tests later