Update requirements.psd1 to Pester 5.3.3

[HeyItsGilbert]

Update the initial module to require Pester 5.3.3

Description

Update the initial module to require Pester 5.3.3. This will be called during the -Bootstrap step.

Related Issue

#33

Motivation and Context

Ensure the initial module will build via Github Actions

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] My code follows the code style of this project.
• [x] My change requires a change to the documentation.
• [x] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [x] I have added tests to cover my changes.
• [x] All new and existing tests passed.