Update DockerFile to avoid error 'npm ERR! Tracker "idealTree" alread…'

[wikijm]

Example of a build process with an error:

docker build -t cyberchef-server . Sending build context to Docker daemon 346.6kB Step 1/8 : FROM node:alpine3.10 ---> fd1f8547e2ff Step 2/8 : LABEL author "Wes Lambert, [email protected]" ---> Using cache ---> f86a769f4bbd Step 3/8 : LABEL description="Dockerised version of Cyberchef server (https://github.com/gchq/CyberChef-server)" ---> Using cache ---> 0412b66fc5a4 Step 4/8 : LABEL copyright "Crown Copyright 2020" ---> Using cache ---> 71bd0a07c39e Step 5/8 : LABEL license "Apache-2.0" ---> Using cache ---> 6eecd557a052 Step 6/8 : COPY . /CyberChef-server ---> 2fbacc2f39e1 Step 7/8 : RUN npm cache clean --force && npm install /CyberChef-server ---> Running in d5758748b069 npm WARN using --force Recommended protections disabled. npm ERR! Tracker "idealTree" already exists

npm ERR! A complete log of this run can be found in: npm ERR! /root/.npm/_logs/2021-10-18T16_19_02_622Z-debug.log The command '/bin/sh -c npm cache clean --force && npm install /CyberChef-server' returned a non-zero code: 1

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