docs: dockerfile ENV LegacyKeyValueFormat

[m0nclous]

Fixed LegacyKeyValueFormat "ENV key=value" warning

[+] Building 17.6s (8/12)
 => [internal] load local bake definitions                                                                                                                                                                                                                                                                     0.0s 
 => => reading from stdin 496B                                                                                                                                                                                                                                                                                 0.0s 
 => [internal] load build definition from Dockerfile                                                                                                                                                                                                                                                           0.0s 
 => => transferring dockerfile: 966B                                                                                                                                                                                                                                                                           0.0s 
 => WARN: LegacyKeyValueFormat: "ENV key=value" should be used instead of legacy "ENV key value" format (line 32)                                                                                                                                                                                              0.0s 
 => WARN: LegacyKeyValueFormat: "ENV key=value" should be used instead of legacy "ENV key value" format (line 33)    

🔗 Linked issue

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

[pkg-pr-new]

npm i https://pkg.pr.new/@nuxt/content@3394

commit: 00f0ded

[farnabaz]

Thanks