CVE-2024-22419: concat built-in can corrupt memory in vyper

concat built-in can write over the bounds of the memory buffer that was allocated for it and thus overwrite existing valid data. The root cause is that the build_IR for concat doesn’t properly adhere to the API of copy functions (for >=0.3.2 the copy_bytes function).

A contract search was performed and no vulnerable contracts were found in production.

Tracked in issue https://github.com/vyperlang/vyper/issues/3737