[Feature] add an option for --profile flag

[iamunnip]

Considering the issue #18, ecrctl needs AWS CLI needs to be configured for executing the login command.
So it's better add a --profile option for handling multiple profiles configured in AWS CLI.

Example command

> ecrctl login --profile <profile-name>

[surajnarwade]

Thanks for the raising the issue. as I mentioned in the other issue. ecrctl needs your AWS credentials but it does not need AWS CLI.

[iamunnip]

Okay thank you.

[surajnarwade]

@iamunnip I have added support for --profile flag, would you be able to test it from the main branch?

[iamunnip]

@surajnarwade Okay, I will test it from main branch, if you provide the right commands.
I don't have any programming experience