Rails/TimeZone cop should allow Time.parse against a fixed string which includes a timezone specifier (bis)

[inkstak]

Is your feature request related to a problem? Please describe.

Similar to #440, we are often use this construct in tests :

Time.parse("2022-10-30 00:00:00 CEST +02:00")

It's especially usefull for explicit summer/winter time :

Time.parse("2022-10-30 00:00:00 CEST +02:00")
 => 2022-10-30 00:00:00 +0200

Time.parse("2022-10-31 00:00:00 CET +01:00")
 => 2022-10-31 00:00:00 +0100

Describe the solution you'd like

If detecting zones abbreviations might be too overwhelming, the cop should be able to detect and allow time offsets from UTC.

Similar to #441 :

-       TIMEZONE_SPECIFIER = /[A-z]/.freeze
+       TIMEZONE_SPECIFIER = /([A-z]|[+-]\d{2}:\d{2})\Z/.freeze

        def attach_timezone_specifier?(date)
-          date.respond_to?(:value) && TIMEZONE_SPECIFIER.match?(date.value.to_s[-1])
+          date.respond_to?(:value) && TIMEZONE_SPECIFIER.match?(date.value.to_s)
        end