Fix #10616 - Default values of DateTime always in English and value “first day of next month” gives an error

[SinergiaCRM]

Description

Fixing #10616

This PR solves two issues.

1. The first one, as described in the issue, it was detected that in the creation/edition view of Studio fields, for fields of type DateTime, the default values to be selected are not shown in the different languages, but always in English.
2. In the second one, it was detected that if the default value “first day of next month” is selected for a field of type “DateTime”, of any module, the instance gives an error that makes it unusable.

Motivation and Context

1. The constructor function has been added next to $app_strings where the labels of the dropdown are collected. Generating the dropdown.
2. Fixed the value “first of next month” that was generating problem, for “first day of next month”.

How To Test This

1. Go to Studio, to any module and add a field.
2. Create a field of type Date and time (DateTime) and check that the list of default values is displayed in the language that the user has selected in the login or has the default instance.
3. Also, check that when selecting “first day of next month”, the field can be saved and displayed correctly without generating an error that prevents access to “Administration”.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Final checklist

• My code follows the code style of this project found here.
• My change requires a change to the documentation.
• I have read the How to Contribute guidelines.