Fix: Patch regex pattern for Github validation

[notsatan]

Description

Apparently, the regex pattern being used to validate if a module-path was a Github repository did not allow for underscores in the user/repository name

go-template/hooks/pre_gen_project.py

Lines 13 to 14 in e146f9e

	# Regex pattern to validate module name - might need some tweaks
	pattern = r"^github.com\/[a-zA-Z0-9\-]+\/[a-zA-Z0-9\-]+\/?$"

This PR closes #53

Type of Change

• 📚 Documentation (Non-breaking change; Changes in the documentation)
• 🔧 Bug fix (Non-breaking change; Fixes an existing bug)
• 🥂 Improvement (Non-breaking change; Improves existing feature)
• 🚀 New feature (Non-breaking change; Adds functionality)
• 🔐 Security fix (Non-breaking change; Patches a security issue)
• 💥 Breaking change (Breaks existing functionality)

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