Update docs/pos/architecture/heimdall/index.md

Co-authored-by: Dra Murphy <149679879+kmurphypolygon@users.noreply.github.com>

Author: hsutaiyu

docs/pos/architecture/heimdall/index.md

@@ -2,11 +2,11 @@
 
 Heimdall is the heart of the Polygon PoS network. It performs the following functions:
 
-- Manages validators
-- Handles block producer selection
-- Facilitates spans
-- Orchestrates the state sync mechanism between Ethereum and Polygon PoS
-- Addresses other essential aspects of the system
+- Manages validators.
+- Handles block producer selection.
+- Facilitates spans.
+- Orchestrates the state sync mechanism between Ethereum and Polygon PoS.
+- Addresses other essential aspects of the system.
 
 It uses the *Cosmos SDK* and a forked version of Tendermint, called *Peppermint*. Here is the Peppermint source: [https://github.com/maticnetwork/tendermint/tree/peppermint](https://github.com/maticnetwork/tendermint/tree/peppermint)