[BUG]: Remove Basic keyword from shift4 API key

Bug Description

While accepting api_key from user in shift4 currently we accept something like Basic c2tfdGVzdF93cjhMYjdqd1FvbwajkhfbQ6.

This Basic Keyword should not be there as if we only want to access the value of the key at some other authorization it would be difficult to extract.

Expected Behavior

The Basic key should be appended in the code like it is done for Bluesnap in bluesnap.rs .

Since we add Basic at code level we can only expect the actual key in the input from the user, rather than expecting the Basic key along with it.

Actual Behavior

Basic as keyword needs to be added in the api_key field under connector_account_details in create connector account api

Have you spent some time to check if this bug has been raised before?

[X] I checked and didn't find similar issue

Have you read the Contributing Guidelines?

[X] I have read the Contributing Guidelines

Are you willing to submit a PR?

No, but I'm happy to collaborate on a PR with someone else

juspay / hyperswitch