refactor(SwingSet): convert run-utils.ts to JS

[michaelfig]

Description

So that SwingSet remains a "Just Javascript" package, convert tools/run-utils.ts from Typescript to Javascript.

Best reviewed without whitespace changes.

Security Considerations

n/a

Scaling Considerations

n/a

Documentation Considerations

n/a

Testing Considerations

n/a

Upgrade Considerations

n/a

[turadg]

I think it's harder to read now but worth it on balance for keeping this package just .js.

[dckc]

I wondered whether the main SwingSet maintainers were aware that some .ts got in to the package. Some spelunking shows it was don in 699d9e1 , which was written by Chip and reviewed by warner. So I'm a little ambivalent about this change.

I'm still don't have enough experience to be comfortable with typescript beyond .d.ts files, so I guess I'm happy in that sense.

[dckc]

I'm a little surprised that there are no changes to package.json to turn off tsx tooling. I suppose those settings are global to the monorepo?

[turadg]

little surprised that there are no changes to package.json to turn off tsx tooling

This file was imported in exactly two places (packages/boot and packages/benchmark), and they both still need the tsx loader.