How to trim() keys from object in javascript?

I have object like this :

const output = 
[
  {
    Email: '[email protected]',
    KolomB: 'Haha',
    KolomC: '6',
    'Kolom D': '3.000.000',
    KolomE: '2 Jan 22'
  },
  {
    Email: '[email protected]',
    KolomB: 'Haha',
    KolomC: '6',
    'Kolom D': '3.000.000',
    KolomE: '2 Jan 22'
  }
]

I want to use trim() for removing space if occurs in object keys.

I was trying with this :

let keys = Object.keys(output[0])
      for (let i = 0; i < keys.length; i++) {
        keys[i].trim()
      }
console.log(keys)

but the result was like this :

keys = [ 'Email', 'KolomB', 'KolomC', 'Kolom D', 'KolomE' ]

The space in Kolom D is still there.

How to do solve that, where’s my mistake for processing the data ?

Please let me know if you need more information if it’s still not enough to solve that.