Add pdf

2 jobs for main in 29 seconds (queued for 2 seconds)
Name Stage Failure
pdf Build
No URL provided, cache will not be downloaded from shared cache server. Instead a local version of cache will be extracted. 
Successfully extracted cache
Executing "step_script" stage of the job script
Using docker image sha256:28dca6642db82aaecbed18101d9966f001e8de6691e1a1718c2927c124d81262 for node:10 with digest node@sha256:59531d2835edd5161c8f9512f9e095b1836f7a1fcb0ab73e005ec46047384911 ...
$ mkdir ebooks
$ gitbook install
/bin/bash: line 122: gitbook: command not found
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1