Update istanbul-instrumented-loader

[pjonsson]

What this PR does

The new package seems to be quite
inactive too, but it's more recently
updated than the current package.

This fixes security issues
in dependencies.

Test me

I don't know anything about Node/JavaScript tooling so I need help with testing this.

Checklist

• There are unit tests to verify my changes are correct or unit tests aren't applicable (if so, write quick reason why unit tests don't exist)
• I've updated relevant documentation in doc/.
• I've updated CHANGES.md with what I changed.
• I've provided instructions in the PR description on how to test this PR.

[pjonsson]

@na9da according to yarn audit on a fully yarn upgraded lockfile, this fixes two critical and one moderate security vulnerability.

If this functionality isn't used, it's probably easier to remove it, and I would be happy to do that instead if that is what you prefer.