fix(module: calendar): fix calendar standard/daylight date bug

PR Checklist

Please check if your PR fulfills the following requirements:

[x] The commit message follows our guidelines: https://github.com/NG-ZORRO/ng-zorro-antd-mobile/blob/master/CONTRIBUTING.md#commit
[ ] Tests for the changes have been added (for bug fixes / features)
[ ] Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Application (the showcase website) / infrastructure changes
[ ] Other... Please describe:

What is the current behavior?

2nd of April is displayed twice when AEDT timezone is used. The 2nd of April is the day when AEDT time is changed to AEST, which leads to incorrect number of hours added to the currentDay variable (24 instead of 25). The bug was identified in the datepicker.base.component.ts file on lie 117.

Issue Number: #866

What is the new behavior?

One hour is added (or subtracted) to the currentDay variable when necessary (AEDT to AEST, AEST to AEDT).

Does this PR introduce a breaking change?

[ ] Yes
[x] No

NG-ZORRO / ng-zorro-antd-mobile