error: Block type should be the same between all runtime apis.
  --> $DIR/mock_only_one_block_type.rs:20:12
   |
20 |     impl Api2<Block2> for MockApi {
   |               ^^^^^^

error: First block type found here
  --> $DIR/mock_only_one_block_type.rs:16:11
   |
16 |     impl Api<Block> for MockApi {
   |              ^^^^^
