docs: proofread upgrade guide

Author: softbeehive

docs/UPGRADE_V1_TO_V2.md

@@ -1,20 +1,21 @@
 # Upgrade guide
 
-Upgrading your vue-stripe-js from v1 to v2.
+Upgrading your Vue Stripe.js from v1 to v2.
 
-Vue Stripe.js v2.0.0 is a major update that makes changes in default choices due to Stripe.js evolution. It was designed with stability in mind. Your upgrade should be smooth and simple.
+v2.0.0 is a major update that introduces changes in default choices due to the evolution of Stripe.js. It was designed with stability in mind, ensuring that your upgrade should be smooth and simple.
 
 ## Breaking changes
 
-ES module is the de-facto standard. Vite is expected to drop commonjs support in 2025. Don't upgrade if you use "require" instead of "import".
+ES modules are the de facto standard. Vite is expected to drop CommonJS support in 2025. Do not upgrade if you are using "require" instead of "import."
 
-- added npm type module
-- removed commonjs export
+- Added npm type module
+- Removed CommonJS export
 
 ## Features
-- Backward-compatible, old implementations should work seamlessly
+
+- Backward-compatible; old implementations should work seamlessly
 - Payment Element is the new default
-- Better TypeScript support
+- Improved TypeScript support
 - Added new examples for Payment, Card, and Express Checkout
 
 ## Upgrade