simplify config generation + atomic removal line

Dockerfile

@@ -22,10 +22,8 @@ RUN if [ "$WIN_BUILD" = "true" ] ; then apt-get -y install mingw-w64; fi
 RUN pip3 install --no-cache-dir -r requirements.txt
 
 # Set up config file and disable atomic by default
-RUN if [ -f "conf/local.yml" ]; then sed -i '/\- atomic/d' conf/local.yml;                                             \
-    else sed -i '/\- atomic/d' conf/default.yml;                                                                       \
-    python3 -c "import app; import app.utility.config_generator; app.utility.config_generator.ensure_local_config();"; \
-    fi
+RUN python3 -c "import app; import app.utility.config_generator; app.utility.config_generator.ensure_local_config();"; \
+    sed -i '/\- atomic/d' conf/local.yml;
 
 # Install golang
 RUN curl -L https://go.dev/dl/go1.17.6.linux-amd64.tar.gz -o go1.17.6.linux-amd64.tar.gz