Migration of gitlab_branch_protection resource from sdkv2 to terraform-provider-framework

Continuation of fix from gitlab-org/terraform-provider-gitlab!1593 (closed) and gitlab-org/terraform-provider-gitlab!1604 (closed).

Description:

gitlab-org/terraform-provider-gitlab!1593 (comment 1436776482)

Fix:

Migration of gitlab_branch_protection resource to terraform-provider-framework and proper extension of update method.