feat: add branch_protection resource (#72)

added terraform tests for the resource

Reviewed-on: https://gitea.com/gitea/terraform-provider-gitea/pulls/72
Co-authored-by: Jörg Markert <joerg.markert@gmail.com>
Co-committed-by: Jörg Markert <joerg.markert@gmail.com>

examples/resources/gitea_repo_branch_protection/resource.tf

@@ -0,0 +1,14 @@
+resource "gitea_repository" "repo" {
+  username  = var.username
+  name      = var.name
+  auto_init = false
+}
+
+resource "gitea_repository_branch_protection" "main" {
+  username = gitea_repository.repo.username
+  name     = gitea_repository.repo.name
+
+  rule_name             = "main"
+  enable_push           = true
+  status_check_patterns = var.branch_protection_patterns
+}