fix dialyzer

.dialyzer-ignore

@@ -4,7 +4,7 @@
 apps/ethereum_jsonrpc/lib/ethereum_jsonrpc.ex:400: Function timestamp_to_datetime/1 has no local return
 lib/block_scout_web/views/layout_view.ex:174: The call 'Elixir.Poison.Parser':'parse!'(any(),#{'keys':='atoms!'}) will never return since the success typing is (binary() | maybe_improper_list(binary() | maybe_improper_list(any(),binary() | []) | byte(),binary() | []),[{atom(),_}]) -> 'false' | 'nil' | 'true' | binary() | ['false' | 'nil' | 'true' | binary() | [any()] | number() | map()] | number() | map() and the contract is (iodata(),'Elixir.Keyword':t()) -> t()
 lib/explorer/repo/prometheus_logger.ex:8
-lib/block_scout_web/views/layout_view.ex:174
+lib/block_scout_web/views/layout_view.ex:175
 lib/explorer/smart_contract/publisher_worker.ex:6
 apps/explorer/lib/explorer/repo/prometheus_logger.ex:8: Function microseconds_time/1 has no local return
 apps/explorer/lib/explorer/repo/prometheus_logger.ex:8: The call 'Elixir.System':convert_time_unit(__@1::any(),'native','microseconds') breaks the contract (integer(),time_unit() | 'native',time_unit() | 'native') -> integer()