chore: update more docs for 1.22

Author: stainless-app[bot]

CONTRIBUTING.md

@@ -9,7 +9,7 @@ $ ./scripts/lint
 
 This will install all the required dependencies and build the SDK.
 
-You can also [install go 1.18+ manually](https://go.dev/doc/install).
+You can also [install go 1.22+ manually](https://go.dev/doc/install).
 
 ## Modifying/Adding code
 

README.md

@@ -35,7 +35,7 @@ go get -u 'github.com/stainless-api/[email protected]'
 
 ## Requirements
 
-This library requires Go 1.18+.
+This library requires Go 1.22+.
 
 ## Usage