message: test: use f-strings in feature_blocksdir.py
diff: @@ -24,10 +24,10 @@ class BlocksdirTest(BitcoinTestFramework):
  initialize_datadir(self.options.tmpdir, 0, self.chain)
  self.log.info("Starting with nonexistent blocksdir ...")
  blocksdir_path = os.path.join(self.options.tmpdir, 'blocksdir')
  - self.nodes[0].assert_start_raises_init_error(["-blocksdir=" + blocksdir_path], 'Error: Specified blocks directory "{}" does not exist.'.format(blocksdir_path))
  + self.nodes[0].assert_start_raises_init_error([f"-blocksdir={blocksdir_path}"], f'Error: Specified blocks directory "{blocksdir_path}" does not exist.')
  os.mkdir(blocksdir_path)
  self.log.info("Starting with existing blocksdir ...")
  - self.start_node(0, ["-blocksdir=" + blocksdir_path])
  + self.start_node(0, [f"-blocksdir={blocksdir_path}"])
  self.log.info("mining blocks..")
  self.nodes[0].generatetoaddress(10, self.nodes[0].get_deterministic_priv_key().address)
  assert os.path.isfile(os.path.join(blocksdir_path, self.chain, "blocks", "blk00000.dat"))
  