.gitconfig: remove codecommit credential helper
.gitconfig: remove codecommit credential helper

CodeCommit credential helper is designed for ONE IAM user or role. When
using more than one, remove the credential helper from the global
config, and use the --local config instead.

MFA will be prompted as required.

In global config, we can specify "helper store" for osssio bitbucket,
and others as required.

felipe1982/dotfiles,felipe1982/dotfiles,felipe1982/dotfiles