Add lints for unclosed files and fix numerous lints in tests

[anacrolix]

Add the temp file lints needed to catch the locked file issue I had on Windows tests here #18197. Also fixes a bunch of other lints that were masked for tests.

[anacrolix]

Pretty sure the failures are unrelated flakey tests.

[AskAlexSharov]

Pretty sure the failures are unrelated flakey tests.

but i can reproduce on macbook

[AskAlexSharov]

commit := func(txn uint64) error {
		err = domains.Flush(ctx, tx)
		require.NoError(t, err)

		err = tx.Commit()
		require.NoError(t, err)

		tx, err = db.BeginTemporalRw(context.Background())
		require.NoError(t, err)
		defer tx.Rollback()

this func is created to create new tx object