Enhance API documentation

[KafayatYusuf]

What type of PR is this?

Check all applicable

• 🍕 Feature
• 🐛 Bug Fix
• 📝 Documentation
• 🧑‍💻 Refactor
• ✅ Test
• 🤖 Build or CI
• ❓ Other (Correction of spelling errors and punctuation)

Related Issue:

• Corrects grammatical errors and punctuation in the markdown
• Removes trailing backslashes

What does this PR do?

• Removes trailing backslashes
• Updates API description
• Add googles docstrings to functions
• Add status response codes (200,400,403,404,408 & 500) to endpoints
• Corrects grammatical errors and punctuation in the markdown
• Contributes to this issue [https://github.com/Enhance API documentation and examples #219]

Consideration:

• Updating the description helps the user to understand what the API is all about
• Removing trailing backslashes help to keep a consistent format and avoid errors
• Status response codes help user to identify and know the responses to expect

How to test ?

Notes for the reviewer. How to test this change?

Screenshots :

Please provide screenshots of the change.

Checklists:

Checklist before requesting review :

• 📖 Read the HOT Code of Conduct: https://docs.hotosm.org/code-of-conduct
• 👷‍♀️ Create small PRs. In most cases, this will be possible.
• ✅ Provide tests for your changes.
• 📝 Use descriptive commit messages.
• 📗 Update any related documentation and include any relevant screenshots.

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