Update CHANGELOG.md

Author: rohitgr7

CHANGELOG.md

@@ -37,10 +37,10 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 - Fix hanging in DDP HPC accelerators ([#5157](https://github.com/PyTorchLightning/pytorch-lightning/pull/5157)
 
 
-- Fix saved filename in ModelCheckpoint if it already exists ([#4861](https://github.com/PyTorchLightning/pytorch-lightning/pull/4861)
+- Fix saved filename in `ModelCheckpoint` if it already exists ([#4861](https://github.com/PyTorchLightning/pytorch-lightning/pull/4861)
 
 
-- Fix reset TensorRunningAccum ([#5106](https://github.com/PyTorchLightning/pytorch-lightning/pull/5106)
+- Fix reset `TensorRunningAccum` ([#5106](https://github.com/PyTorchLightning/pytorch-lightning/pull/5106)
 
 
 ## [1.1.1] - 2020-12-15