Use PyUpgrade to upgrade to Python 3.8 syntax

[moi15moi]

Run: pre-commit run pyupgrade --all-files

With this .pre-commit-config.yaml file:

repos:
-   repo: https://github.com/asottile/pyupgrade
    rev: v3.19.1
    hooks:
    -   id: pyupgrade
        args: [--py38-plus]

[moi15moi]

@junkmd Do you think this could be merged easily?

[junkmd]

@moi15moi

I appreciate the work done in this PR.
However, to make the review process smoother, I’d like to suggest splitting it into more focused changes.

I believe it would be ideal to group files by topic—meaning each PR should focus on a specific review point that spans multiple files.

The major updates in this PR can be grouped into three categories:

1. Removing (object) from class definitions (e.g.: class Foo(object): -> class Foo:)
2. Updating super() calls to use the modern style (e.g.: super(Foo, self).mth_or_attr -> super().mth_or_attr)
3. Standardizing OSError aliases (e.g. except WindowsError: / except IOError: -> except OSError:)

There are also updates related to string formatting, but I think it would be more beneficial to advance the f-string migration discussed in enthought#657 (You can feel free to address that issue).

Other minor fixes are also included, but for now, I think it’s fine to keep them together in one PR.

Let’s first focus on these three PRs plus the f-string issue, and then we can consider how to handle the remaining fixes.

Would you be open to restructuring the PR this way?