Refactor Docker build to override default config instead of system (#63)

# Description
Refactor Docker overlay/build to override default config instead of
System
Fix small typo in `README.md`

# Issues
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# Other Notes
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Dockerfile

@@ -7,7 +7,8 @@ LABEL vendor=neon.ai \
 # Build argument for specifying extras
 ARG EXTRAS
 
-ENV OVOS_CONFIG_BASE_FOLDER=neon \
+ENV OVOS_DEFAULT_CONFIG=/opt/neon/neon.yaml \
+    OVOS_CONFIG_BASE_FOLDER=neon \
     OVOS_CONFIG_FILENAME=neon.yaml \
     XDG_CONFIG_HOME=/config
 # Set the ARG value as an environment variable

README.md

@@ -87,7 +87,7 @@ docker build --build-arg EXTRAS=gradio -t ghcr.io/neongeckocom/neon-iris:latest
 To build the Docker image with websat extras, run:
 
 ```bash
-docker build --build-arg EXTRAS=websat -t ghcr.io/neongeckocom/neon-iris:latest .
+docker build --build-arg EXTRAS=web_sat -t ghcr.io/neongeckocom/neon-iris:latest .
 ```
 
 ### Running