Allow custom modloader versions for auto curseforge (#3759)

examples/auto-curseforge/fabric-custom-loader/docker-compose.yml

@@ -0,0 +1,22 @@
+services:
+  mc:
+    image: itzg/minecraft-server
+    environment:
+      EULA: "TRUE"
+      MODPACK_PLATFORM: AUTO_CURSEFORGE
+      # Allocate API key from https://console.curseforge.com/
+      CF_API_KEY: ${CF_API_KEY}
+      # Example of overriding modloader version for a Fabric modpack
+      # Refer to https://docker-minecraft-server.readthedocs.io/en/latest/types-and-platforms/mod-platforms/auto-curseforge/#api-key
+      CF_SLUG: "cobblemon-fabric"
+      # Override the mod loader version from the modpack
+      CF_MOD_LOADER_VERSION: "0.16.14"
+      MEMORY: "4G"
+    ports:
+      - "25565:25565"
+    volumes:
+      - ./data:/data
+    stdin_open: true
+    tty: true
+
+# See https://docker-minecraft-server.readthedocs.io/en/latest/types-and-platforms/mod-platforms/auto-curseforge/#custom-modloader-versions