Description:
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As discussed in https://externals.io/message/114669

DateTimeZone silently falls back to UTC when providing an offset with seconds:

https://3v4l.org/9ZrK6

It should either work as expected with such an input, or if this is unsupported (which could make sense), it should throw an exception.

Test script:
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echo (new DatetimeZone('+01:45:30'))->getName();

Expected result:
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+01:45:30

Actual result:
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+00:00