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/advanced/backend/taxes/inclusive-pricing.md

@@ -21,7 +21,7 @@ This can be useful when some countries have the same currency but have different
 
 Then, Medusa handles calculating the tax amount using the tax rate and the tax-inclusive price. This is managed in the backend and relayed to accounting and analytics tools.
 
-## How is Tax Inclusivity Defined?
+## How is Tax Inclusivity Defined
 
 Tax inclusivity can be toggled for regions, currencies, price lists, and shipping options either during creation or while editing. This is represented by the boolean attribute `includes_tax` available in the entities `Region`, `Currency`, `PriceList`, and `ShippingOption`. By default, this attribute is set to `false`.
 
@@ -29,7 +29,7 @@ If you want to enable or disable this attribute for any of these entities, you c
 
 The value set for these entities can affect whether line items and shipping methods are tax inclusive or not.
 
-### How is Tax Inclusivity Defined for Line Items?
+### How is Tax Inclusivity Defined for Line Items
 
 :::info
 
@@ -44,7 +44,7 @@ The `LineItem` entity also has the `includes_tax` attribute. The value of this f
 - Or a price list that includes the product variant associated with the line item has the `includes_tax` attribute set to `true`, and the tax-inclusive amount of one of the variant’s prices in the price list is less than the original price of the variant;
 - Or one of the variant’s prices in the price list uses a currency or region that has the `includes_tax` attribute set to `true`, and the tax-inclusive amount of the price is less than the original price of the variant.
 
-### How is Tax Inclusivity Defined for Shipping Methods?
+### How is Tax Inclusivity Defined for Shipping Methods
 
 :::info
 

docs/content/advanced/backend/taxes/manual-calculation.md

@@ -8,7 +8,7 @@ By default, taxes are automatically calculated by Medusa during checkout. This b
 
 If you disable this behavior, you must manually trigger taxes calculation. When taxes are calculated, this means that requests will be sent to the tax provider to retrieve the tax rates.
 
-## How to Manually Calculate Taxes in Checkout?
+## How to Manually Calculate Taxes in Checkout
 
 This section explores different ways you can calculate taxes based on your purpose.