fix: ignore dollar replacement sequences in file paths

[charlessuh]

When using string.replace as a templating engine, care must be taken to escape dollar signs as they can be interpreted as replacement patterns: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/replace#specifying_a_string_as_a_parameter

Note yarn uses a special $$virtual folder in some circumstances, so this can break setups involving yarn.

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[charlessuh]

@googlebot I signed it!

[AppVeyorBot]

✅ Build karma 2944 completed (commit 2046e54eb6 by @charlessuh)

[karmarunnerbot]

✅ Build karma 547 completed (commit 2046e54eb6 by @charlessuh)

[karmarunnerbot]

✅ Build karma 546 completed (commit 2046e54eb6 by @charlessuh)

[devoto13]

Thanks for a PR @charlessuh! However, I think the approach from #3531 is better as it targets the root cause of the problem and does not create an implicit dependency between the generation of URLs and how we format them into the page body.

If you're interested in this fix, maybe you can build on top of that PR and fix the comment there, so we can get it in?

[charlessuh]

Ah, awesome.