chore: replace dtslint with dtslint-like rules in tslint-etc

[cartant]

Description:

This PR removes dtslint and replaces it with an expect-type rule - in tslint-etc - that is a modified version of the expect rule from the dtslint package (which is MIT licensed). Essentially, this PR reduces the number of moving parts in the type tests.

The modified rule uses the locally-installed typescript - i.e. the typescript version specified in the RxJS package.json file - and removes the performance-related code that attempts to write profiling data to the caller's home directory.

Instead of running dtslint, we can now run tslint directly - passing it the tsconfig.json and the tslint.json files that are in the spec-dtslint directory - and can be sure that dtslint isn't doing anything weird in its implementation.

Also, I've added an expect-deprecation rule to tslint-etc which will allow us to ensure that our deprecations are working as they should, like this:

of<number>(); // $ExpectDeprecation
of(); // $ExpectNoDeprecation

I'll start adding more deprecation-related tests once/if this is merged.

And there is a no-dtslint-typo rule to catch some of the invalid dtslint-like expectations - like these - that have crept into the codebase.

Related issue (if exists): #4871