Repro

{
  "rules": {
    "@typescript-eslint/no-unused-expressions": "error"
  }
}

module MyModule {
    'use strict';
}

Expected Result
Should not complain

Actual Result

demo.ts(1,5): error @typescript-eslint/no-unused-expressions : 
Expected an assignment or function call and instead saw an expression.

Same problem was happening with no-unused-expressions from eslint (but i upgraded to ts-eslint one).

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