[jdbc] Server timezone seems overriden by server header

[chernser]

Describe the bug

all of these assertions failed with datetimes and timezones conversions, for example:
Setting :report-timezone = "America/Los_Angeles"
diff: - {:month "2012-12-01T00:00:00-08:00",
:quarter "2012-10-01T00:00:00-07:00",
:week "2012-12-23T00:00:00-08:00",
:year "2012-01-01T00:00:00-08:00"}
+ {:month "2012-11-30T00:00:00-08:00",
:quarter "2012-09-30T00:00:00-07:00",
:week "2012-12-22T00:00:00-08:00",
:year "2011-12-31T00:00:00-08:00"}

Broken in 0.6.4

Steps to reproduce

Expected behaviour

Code example

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Configuration

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• Client version:
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ClickHouse server

• ClickHouse Server version:
• ClickHouse Server non-default settings, if any:
• CREATE TABLE statements for tables involved:
• Sample data for all these tables, use clickhouse-obfuscator if necessary