Use backquotes for code block for consistency

README.md

@@ -53,9 +53,9 @@ In order to use Astronomer, you'll need a GitHub token with `repo` read rights.
 
 Run the astronomer docker image like such:
 
-~~~bash
+```bash
 docker run --rm -t -e GITHUB_TOKEN=$TOKEN -v "/path/to/cache:/data" ullaakut/astronomer repositoryOwner/repositoryName
-~~~
+```
 
 * The `-t` flag allows you to get a colored output. You can remove it from the command line if you don't care about this.
 * The `-e GITHUB_TOKEN=<your_token>` option is mandatory. The GitHub API won't authorize any requests without it.