Stateful and Stateless Tests in Random Timezones with Timezone Respect in Protobuf and GraphiteMergeTree

Now we ran stateful and stateless tests in random timezones. Fixes #12439. Reading String as DateTime and writing DateTime as String in Protobuf format now respect timezone. Reading UInt16 as DateTime in Arrow and Parquet formats now treat it as Date and then converts to DateTime with respect to DateTime's timezone, because Date is serialized in Arrow and Parquet as UInt16. GraphiteMergeTree now respect time zone for rounding of times. Fixes #5098. Author: @alexey-milovidov. #15408 (alesapin).