[no-func-assign] Duplicates TypeScript's TS2539 error

[OliverSieweke]

Recommended ESLint rules that are already handled by TypeScript are turned off in plugin:@typescript-eslint/recommended.
The recommended no-func-assign rule should be included in the list as it triggers an ESLint as well as a TypeScript error.

Repro

{
  "extends": [
    "eslint:recommended",
    "plugin:@typescript-eslint/eslint-recommended",
    "plugin:@typescript-eslint/recommended"
  ]
}

function foo() {}
foo = bar;

Expected Result

A simple TypeScript error for line 2:

• TS2539: Cannot assign to 'foo' because it is not a variable.

Actual Result

A duplicate error for line 2, one coming from TypeScript the other one coming from ESLint:

• TS2539: Cannot assign to 'foo' because it is not a variable.
• ESLint: 'foo' is a function.(no-func-assign)

Additional Info

Versions

package	version
@typescript-eslint/eslint-plugin	2.3.0
@typescript-eslint/parser	2.3.0
TypeScript	3.6.3
ESLint	6.4.0
node	10.16.3
npm	6.9.0

[bradzacher]

Thanks for the suggestion!
I think it's a good idea to add this to the list.

We are unable to make changes to the recommended sets without a breaking change, so we'll leave this open for now - but I've added it to the list of things to get in with the 3.0 release.

[bradzacher]

consolidated eslint-recommended changes in #1273