A&R - Export Report - Update wording for column names

## Description
This ticket is to update the wording for column names to match the changes we made on the UI via [BRS-605: UI Refinements - read only views](https://bcparksdigital.atlassian.net/browse/BRS-605)

Group Camping
* Wording : Change **_Youth_** > **_Youths_**
* Wording: Change **_Adult_** > **_Adults_**
* Wording: Change **_Children_** > **_Kids_**
* Wording: Change **_Group nights_** > **_Youth group nights_**

Backcountry cabins
* Wording: Change **_Adult_** > **_Adults_**
* Wording: Change **_Child_** > **_Youths_**
* Wording: Change **_Children_** > **_Youths_**

## Acceptance Criteria:
* Update column names to match the new wording changes applied to the UI

## Notes

## Attachments

## Linked issues

relates to
- [x] ~[BRS-605](https://bcparksdigital.atlassian.net/browse/BRS-605)~

Start by locating the backend entry point that builds the A&R export report and the definitions for its Group Camping and Backcountry cabins column names. Compare those headers with the wording listed in the issue, then verify that the generated export uses the updated names for every listed column.

Written by the indexing model from the issue text.