Add CodeLingo Tenet to fix missing close file

codelingo.yaml

@@ -0,0 +1,4 @@
+tenets:
+- import: codelingo/effective-go
+- import: codelingo/code-review-comments
+- import: codelingo/rfjakob-gocryptfs

tests/fsck/fsck_test.go

@@ -85,6 +85,7 @@ func TestExampleFses(t *testing.T) {
 			t.Errorf("fsck returned code %d but fs should be clean", code)
 		}
 	}
+	dirfd.Close()
 }
 
 // TestTerabyteFile verifies that fsck does something intelligent when it hits