docs: integrate Vale for documentation linting (#2242)

* added value rules

* resolved errors raised by vale

* added github action

* fixes to github action

* added details in contribution guidelines

* added rule for numbers

* limited checks to errors

docs/content/usage/configurations.md

@@ -71,7 +71,7 @@ npm install dotenv --save
 
 ## Database Configuration
 
-Medusa supports 2 database types: SQLite and PostgreSQL.
+Medusa supports two database types: SQLite and PostgreSQL.
 
 :::tip
 
@@ -81,7 +81,7 @@ You can use SQLite for development purposes, however, it’s recommended to use
 
 ### SQLite Configurations
 
-For SQLite you mainly need 2 configurations:
+For SQLite you mainly need two configurations:
 
 ```jsx
 module.exports = {
@@ -103,7 +103,7 @@ Before getting started with configuring PostgreSQL, you should have created a Po
 
 :::
 
-For PostgreSQL you mainly need 2 configurations:
+For PostgreSQL you mainly need two configurations:
 
 ```jsx
 module.exports = {
@@ -181,9 +181,9 @@ You can learn more about Subscribers and events in the [Subscriber documentation
 
 :::
 
-## JSON Web Token (JWT) Secret
+## JWT Secret
 
-Medusa uses JWT to handle user authentication. To set the JWT secret:
+Medusa uses JSON Web Token (JWT) to handle user authentication. To set the JWT secret:
 
 ```jsx
 module.exports = {
@@ -353,6 +353,6 @@ It is recommended to use environment variables to store values of options instea
 
 ## What’s Next 🚀
 
-- Check out our [Next.js](../starters/nextjs-medusa-starter.md) and [Gatsby](../starters/gatsby-medusa-starter.md) starter storefronts.
+- Check out the [Next.js](../starters/nextjs-medusa-starter.md) and [Gatsby](../starters/gatsby-medusa-starter.md) starter storefronts.
 - Install the [Medusa admin](../admin/quickstart.md).
 - Learn about [deploying the Medusa server](../deployments/server/index.mdx).