feat: create SpdxLicense

[alestiago]

Description

Creates the SpdxLicense enumeration using the brick.

This change anticipates #771 and #848

Changes:

• Generates spdx_license.gen.dart in the Very Good CLI project
• Excludes gen.dart files from coverage since they are already be tested bn the generator
• Includes a post_gen hook to ensure the generated file is formatted to avoid formatter failures on Very Good CLI
• Remove redundant "..." on pre_gen logged message, since the progress already suffixes "..."

Type of Change

• ✨ New feature (non-breaking change which adds functionality)
• 🛠️ Bug fix (non-breaking change which fixes an issue)
• ❌ Breaking change (fix or feature that would cause existing functionality to change)
• 🧹 Code refactor
• ✅ Build configuration change
• 📝 Documentation
• 🗑️ Chore