Fix configs in docker builds (#14747)

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## Changes Proposed
- This fixes an issue where the .conf files aren't properly generated for the docker build
  - With this issue, the dbimport service in the docker compose file would fail to start due to insufficient config. 
  - related to PR #14707
- create a ".user" file extension for custom configs in `env/docker/etc/`
- Layers the ".dockerdist" file and the ".user" file over the ".dist" file (in that order), and then copies the ".dist" file to the base ".conf" file
- Docker specific config changes go in the ".dockerdist" file and should still be committed to the repo
- User specific config changes go in ".user" file and should not be committed to the repo
- If the ".dist" file and the base ".conf" file are different, the ".conf" will be backed up before the ".dist" file is copied into it

## Issues Addressed:
<!-- If your fix has a relating issue, link it below -->
- There isn't a specific issue, however this was reported and discussed in discord over the course of yesterday and today

## SOURCE:
<!-- If you can, include a source that can strengthen your claim -->

## Tests Performed:
<!-- Does it build without errors? Did you test in-game? What did you test? On which OS did you test? Describe any other tests performed -->
- Executing commands to build and start the game server
- after creating an account, I can log in and play without any issues. 


## How to Test the Changes:
<!-- Describe in a detailed step-by-step order how to test the changes -->

1.  Execute commands
   
    ```bash
    $ ./acore.sh docker clean:build && ./acore.sh docker build:nocache && ./acore.sh docker start:app
    ```
2. Create account and log in as normal

## Known Issues and TODO List:
<!-- Is there anything else left to do after this PR? -->

- The largest issue that comes to mind is this is a breaking change for docker users (though, so was the change that caused this)
  - Docker users (and nobody else, of course) can no longer use the ".conf" for custom changes in docker setups. 
  - Their custom changes will have to be migrated to the ".user" file
  - Since the old ".conf" file is backed up, users should have minimal trouble copying the changes in the old ".conf" file to the new ".user" file

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edit: link related PR

1 files changed, 1 insertions, 3 deletions

diff --git a/.gitignore b/.gitignore
index a6cbe335af..11d0e4fe4d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,9 +22,7 @@
 !/env/docker/data/.gitkeep
 !/env/docker/etc/
 /env/docker/etc/*
-!/env/docker/etc/authserver.conf.dockerdist
-!/env/docker/etc/worldserver.conf.dockerdist
-!/env/docker/etc/dbimport.conf.dockerdist
+!/env/docker/etc/*.conf.dockerdist
 !/env/docker/logs/.gitkeep
 /.env*
 /apps/joiner