Reusable merge of male/female names into first_names list

[robosoul]

Is your feature request related to a problem? Please describe.
For following locales:

• src/main/resources/en-PH.yml
• src/main/resources/fi-FI.yml
• src/main/resources/nb-NO.yml

Male and female first names are simply copy/pasted to first_name list. Example from en-PH:

      male_first_name: [Michael, Christian, Jeffrey, Jayson, Richard, Ryan, Jonathan, Joseph, Alvin, Marvin, Joel, Christopher, Julius, Angelo, Emmanuel]
      female_first_name: [Michelle, Jennifer, Catherine, Mary Grace, Angelica, Maricel, Rowena, Joan, Jocelyn, Mary Ann, Jessica, Arlene, Melanie, Mary Jane, Janice, Rosemarie, Christine, Marjorie, Analyn, Josephine]
      first_name: [Michael, Christian, Jeffrey, Jayson, Richard, Ryan, Jonathan, Joseph, Alvin, Marvin, Joel, Christopher, Julius, Angelo, Emmanuel, Michelle, Jennifer, Catherine, Mary Grace, Angelica, Maricel, Rowena, Joan, Jocelyn, Mary Ann, Jessica, Arlene, Melanie, Mary Jane, Janice, Rosemarie, Christine, Marjorie, Analyn, Josephine]     

Describe the solution you'd like
We should use most common (reusable) approach, where first_name is combo (not copy/pasted) of male_first_name and female_first_name values:

      first_name:
        - "#{male_first_name}"
        - "#{female_first_name}"

Describe alternatives you've considered
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Additional context
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