Update contributors.yml

[IssaHanou]

original template: https://github.com/github/contributors?tab=readme-ov-file#example-workflows

[IssaHanou]

do we need this step too:

      - name: Get dates for last month
        shell: bash
        run: |
          # Calculate the first day of the previous month
          start_date=$(date -d "last month" +%Y-%m-01)
  
          # Calculate the last day of the previous month
          end_date=$(date -d "$start_date +1 month -1 day" +%Y-%m-%d)
  
          #Set an environment variable with the date range
          echo "START_DATE=$start_date" >> "$GITHUB_ENV"
          echo "END_DATE=$end_date" >> "$GITHUB_ENV"

[IssaHanou]

- name: Get dates for last month
    shell: bash
    run: |
      # Calculate the first day of the previous month
      start_date=2023-01-01

      # Calculate the last day of the previous month
      end_date=$(date -d "$start_date +1 month -1 day" +%Y-%m-%d)

      #Set an environment variable with the date range
      echo "START_DATE=$start_date" >> "$GITHUB_ENV"
      echo "END_DATE=$end_date" >> "$GITHUB_ENV"