chore: change short month name for August for consistency with moment.js configuration

[crestf]

Description:
I have noticed that ngx-bootstrap uses the 'id' locale configuration, based on moment.js locale configuration. However, there is a difference in the short month name for 'August'—moment.js uses 'Agt,' while ngx-bootstrap uses 'Ags.' This inconsistency leads to a different display in my project, which utilizes both ngx-bootstrap and moment.js configurations.

As an Indonesian myself, I propose following moment.js locale configuration, as it has become more common lately to abbreviate the month name 'August' as 'Agt.'

Reference to moment.js locale configuration: https://github.com/moment/moment/blob/develop/locale/id.js#L19
Reference to ICU locale for Indonesia (id-ID): https://www.localeplanet.com/icu/id-ID/index.html

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