Remove @ts-expect-error comments from TS 3.x migration

[aabmass]

I used the ts-migrate script to add @ts-expect-error to silence new TS errors introduced in migration from TypeScript 2.x to 3.x (#907). For example

opencensus-node/packages/opencensus-core/src/internal/cls-ah.ts

Line 95 in 9bd4f11

// @ts-expect-error ts-migrate(2345) FIXME: Argument of type 'IArguments' is not assignable to... Remove this comment to see the full error message

Definitive list: https://github.com/census-instrumentation/opencensus-node/search?q=ts-migrate

[alaminShaheen]

There are more than 20 such comments. Do you want all of them removed?

[aabmass]

Yes if possible, but it's low priority as this project has been mostly superseded by OpenTelemetry 🙂 Would you like to help out on this?