Constant sp_maybe_compressed_blob::CODE_BLOB_BOMB_LIMIT

pub const CODE_BLOB_BOMB_LIMIT: usize = 50 * 1024 * 1024; // 0x0000_0000_0320_0000usize

A recommendation for the bomb limit for code blobs.

This may be adjusted upwards in the future, but is set much higher than the expected maximum code size. When adjusting upwards, nodes should be updated before performing a runtime upgrade to a blob with larger compressed size.