Implement capability to authenticate request with API Key Auth mechanism

[kannananil]

Note: This issue is dependent on the #77 which implements the Basic UI Layout for the authentication tab

• Given the user is on the Authentication tab
  When the user selected API Key Authentication as type
  Then the user should be able to see two text fields for Key and Value to input the credentials

• Given the user selected the API Key Authentication as type and Added the credentials
  When the user triggers the request
  Then the request should be sent with given Key and Value in headers

[Aman-shabbas]

Hi @kannananil, I'm interested in this issue, can I work on this?

[kannananil]

@Aman-shabbas, sure please proceed I have assigned the issue to you