chore: Remove binary from repository (#105)

A compiled `terraform-provider-gitea` was added to the repository in
#85. Surely this is a mistake, this file definitely doesn't belong in
the git repository.

Reviewed-on: https://gitea.com/gitea/terraform-provider-gitea/pulls/105
Co-authored-by: Mathieu Lemay <[email protected]>
Co-committed-by: Mathieu Lemay <[email protected]>

Author: mathieu-lemay