Fix most linting errors

[bakkot]

This fixes a majority of the errors you get when running npm run build -- --lint-spec. There's two left:

• ecmarkup doesn't know what the "normative-optional-legacy" attribute is supposed to mean. There's some code which says "ecmarkup only supports annotating algorithm steps with a single attribute", but that's false; on the other hand it doesn't know what "normative-optional" or "legacy" mean as step attributes either. Also https://github.com/tc39/proposal-import-attributes/pull/133 is maybe changing that anyway.
• this step makes reference to a _record_ alias which hasn't been introduced. I don't know what that's supposed to be, so I left it alone.

You can't enforce linting without fixing both of these, alas, and the first is not fixable without an update to ecmarkup - which I can do if we're decided on what is needed here.

[nicolo-ribaudo]

Thank you! For the second point, would this be valid or do I need to explicitly write a loop?

1. If _referrer.[[LoadedModules]] contains a Record _record whose [[Specifier]] is _moduleRequest.[[Specifier]] and AttributesEqual(_record.[[Attributes]], _moduleRequest_.[[Attributes]]) is true, then

[bakkot]

Ecmarkup doesn't recognize "whose", but it does recognize "such that", so contains a Record _record_ such that _record_.[[Specifier]] should work.

[nicolo-ribaudo]

Thank you! Down to a single error now; I'll follow up on the first point once #133 is merged.