fix: handle trailing slash at end of API endpoint

Updated the code that builds the URL for the GraphQL API to handle the situation where the `api_key_endpoint` setting includes a trailing `/`.

spacelift/provider.go

@@ -225,7 +225,11 @@ func buildClientFromToken(token string) (*internal.Client, error) {
 
 func buildClientFromAPIKeyData(d *schema.ResourceData) (*internal.Client, error) {
 	// Since validation runs first, we can safely assume that the data is there.
-	endpoint := fmt.Sprintf("%s/graphql", d.Get("api_key_endpoint").(string))
+
+	// Handle / at api_key_endpoint
+	endpoint := strings.TrimSuffix(d.Get("api_key_endpoint").(string), "/")
+	endpoint = fmt.Sprintf("%s/graphql", endpoint)
+
 	apiKeyID := d.Get("api_key_id").(string)
 	apiKeySecret := d.Get("api_key_secret").(string)