Formatted the calendar widget

[akshitrattan]

Pull Request for Issue #36933 .

Summary of Changes

solved issue number 3/3. Stylized the time drop-down menu according to bootstrap 4 and centred the calendar table in the widget for the calendar to look more symmetrical

Testing Instructions

Open the calendar widget in any of the tabs you wish to, notice the change in the buttons from the previous versions

Actual result BEFORE applying this Pull Request

calendar looked like this

Expected result AFTER applying this Pull Request

it should look like this

Documentation Changes Required

No changes required

[HLeithner]

This pull request has automatically rebased to 4.2-dev.

[joomla-bot]

This pull requests has been automatically converted to the PSR-12 coding standard.

[chmst]

I have tested this item :white_check_mark: successfully on 259bc23c484f1faa3c71227f0bdb10f2712ba1c5

Looks good for me. Especially in languages with longer words.

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[HLeithner]

This pull request has been automatically rebased to 4.3-dev.

[MojoMojosoup]

I have tested this item :white_check_mark: successfully on cfef2214305dfc9160e29d8484ec7c030f39f980

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[cyrez]

I have tested this item :red_circle: unsuccessfully on cfef2214305dfc9160e29d8484ec7c030f39f980

Just find your PR, while i've done one to improve calendar form field datetime picker #40761

I've set my test as unsuccessfully, as the colspan changes may have issues depending on the form field settings (with or without weeknumbers, am/pm...) And the css changes are not flexible to work in different cases (language, settings...).

You can check my PR #40761 and see what i did there (with a bit more styling for other elements, such as footer buttons) ;-)

Thanks! Cyril

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[obuisard]

Thank you Akshit @akshitrattan for this PR. After review, I think this is not flexible enough and results may vary depending on the languages used. I am closing the PR in favor of PR https://github.com/joomla/joomla-cms/pull/40761. Thank you for your contribution on this!