Implemented method JSDocs not behaving correctly for @param

*TS Template added by @mjbvz* **TypeScript Version**: 4.0.0-dev.20200518 **Search Terms** - completionEntryDetails - jsdoc - tags --- <!-- ⚠️⚠️ Do Not Delete This! bug_report_template ⚠️⚠️ --> <!-- Please read our Rules of Conduct: https://opensource.microsoft.com/codeofconduct/ --> <!-- Please search existing issues to avoid creating duplicates. --> <!-- Also please test using the latest insiders build to make sure your issue has not already been fixed: https://code.visualstudio.com/insiders/ --> <!-- Use Help > Report Issue to prefill these. --> - VSCode Version: 1.45.0 - OS Version: Ubuntu 20.04 Steps to Reproduce: 1. Add JSDocs to an interface, and implement that interface in a class ```ts interface Sample { /** * Does some important work * @param name Name of employee working * @param age Age of employee */ doWork(name: string, age: number): void; } let s: Sample; class Concrete implements Sample { doWork(name: string, age: number) { // Nothing to do } } let c: Concrete; ``` 2. Attempt to access intellisense for the class, and notice the @param information has not been picked up from the interface.  <!-- Launch with `code --disable-extensions` to check. --> Does this issue occur when all extensions are disabled?: Yes