feat(expo): read .env file in upload script

[quinlanj]

📢 Type of change

• Bugfix
• New feature
• Enhancement
• Refactoring

📜 Description

Read from .env file if it exists in the user's project directory, based on #3546 (comment)

Fixes #3569

Most of the expo commands are of this form:

1. Set NODE_ENV to development if unset (unless if the command is expo export, where the metro bundler will output differently depending on NODE_ENV so we default it to production)
2. Read from .env file - @expo/env is a dependency of the expo/cli so we make a best effort to load it at runtime.

💡 Motivation and Context

💚 How did you test it?

test project

📝 Checklist

• I reviewed submitted code
• I added tests to verify changes
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled
• All tests passing
• No breaking changes

🔮 Next steps

[krystofwoldrich]

Thank you, looks good. 🚀