title: Can't install package ‘ggpmisc’ is not available (for R version 3.5.0)
body: <p>I'm trying to install ‘ggpmisc’ package in my Dockerfile, and I got the message : </p>
  
  <pre><code>Installing package into ‘/usr/local/lib/R/site-library’
  (as ‘lib’ is unspecified)
  Warning: unable to access index for repository https://cloud.r-project.org/src/contrib:
  cannot open URL 'https://cloud.r-project.org/src/contrib/PACKAGES'
  Warning message:
  package ‘ggpmisc’ is not available (for R version 3.5.0) 
  </code></pre>
  
  <p>How can I fix it?</p>