Apply suggestions from code review

Author: Borda

CHANGELOG.md

@@ -15,7 +15,7 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
 - Fixed process rank not being available right away after `Trainer` instantiation ([#6941](https://github.com/PyTorchLightning/pytorch-lightning/pull/6941))
 - Fixed `sync_dist` for tpus ([#6950](https://github.com/PyTorchLightning/pytorch-lightning/pull/6950))
-- Fixed `AttributeError for `require_backward_grad_sync` when running manual optimization with sharded plugin ([#6915](https://github.com/PyTorchLightning/pytorch-lightning/pull/6915))
+- Fixed `AttributeError` for `require_backward_grad_sync` when running manual optimization with sharded plugin ([#6915](https://github.com/PyTorchLightning/pytorch-lightning/pull/6915))
 - Fixed `--gpus` default for parser returned by `Trainer.add_argparse_args` ([#6898](https://github.com/PyTorchLightning/pytorch-lightning/pull/6898))
 - Fixed TPU Spawn all gather ([#6896](https://github.com/PyTorchLightning/pytorch-lightning/pull/6896))
 - Fixed `EarlyStopping` logic when `min_epochs` or `min_steps` requirement is not met ([#6705](https://github.com/PyTorchLightning/pytorch-lightning/pull/6705))