Does this issue occur when all extensions are disabled?: Yes

Version: 1.79.0 (user setup)
Commit: b380da4
Date: 2023-06-07T14:26:35.552Z
Electron: 22.5.5
Chromium: 108.0.5359.215
Node.js: 16.17.1
V8: 10.8.168.25-electron.0
OS: Windows_NT x64 10.0.22621

Typescript sample code:

namespace MyNamespace {
  export function sub(a: number, b: number): number {
    return a + b;
  }
}

function addNumbers(a: number, b: number): number {
  return a + b;
}

function caller(a: number, b: number): number {
  return addNumbers(1, 2) + MyNamespace.sub(1, 2);
}

Steps to Reproduce:

1. Use sample code and do a call hierarchy on function caller to show calls from the function.
2. On the call hierarchy tree view result, hover over item "addNumbers" to display tooltip.

Actual result:
A dash "-" is added after the function name when there are no function details to display in the tooltip.

Other notes:
It looks like the dash "-" should only be added when the function has details, such as