fix: Function is Test-AcceleratorRequirement not Test-AcceleratorRequirements (#323)

# Pull Request

## Issue

#322 

## Description

One character fix. (The PowerShell function is not plural).

## License

By submitting this pull request, I confirm that my contribution is made
under the terms of the projects associated license.

Author: lovelysandwich

README.md

@@ -31,7 +31,7 @@ To check the requirements, run these commands:
 
 ```pwsh
 Install-Module -Name ALZ
-Test-AcceleratorRequirements
+Test-AcceleratorRequirement
 ```
 
 ## Contributing