fix: return a 400 error on invalid address

[wa0x6e]

🧿 Current issues / What's wrong ?

When using submit a POST with an invalid address, it returns a 500 error.
User input error should throw a 400 error, and should not be logged as an error in the error monitoring system.

💊 Fixes / Solution

Fix #137
Fix SNAPSHOT-RELAYER-3

Fail early on invalid address, and return a 400 error

🚧 Changes

• Check for address validity early, and fail with 400 code on invalid address
• Do not log invalid address error on Sentry

🛠️ Tests

• N/A

[ChaituVR]

utAck