title: ggplot `facet_grid` label cut off
body: <p>In <code>ggplot</code>, when using <code>facet_grid(..., space = "free_y")</code> and the number of points within a group is small, the facet title gets cut off.</p>
  
  <p>For example...</p>
  
  <pre><code>library(tidyverse)
  
  d &lt;- tibble(
    x = factor(1:40),
    y = rnorm(40),
    g = c(rep("GROUP 1", 39), "GROUP 2")
  )
  
  ggplot(d) +
    aes(x = x, y = y) +
    geom_col() +
    facet_grid(g ~ ., scales = "free_y", space = "free_y") +
    coord_flip() +
    theme(
      strip.text.y = element_text(angle = 0, size = rel(4))
    )
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/n2KKK.png" alt="ggplot with facet strip text cut-off"></p>
  
  <p>Is there any way to get the <code>GROUP 2</code> text to not be cut-off at the facet grid margins? I'm aware that I can just stretch the plot, but that's not really a satisfying solution -- after all, there's all that margin space between facets! Is there a way to get the label to just bleed into those?</p>