Since Bundler 2.4.19, including in Ruby 3.2.3, it's possible to define
the Ruby version in the Gemfile by indicating which file contains the
version [1].
There are at least two practical cases where this is an advantage.
First, people using RVM in development will no longer accidentally run
the application using the wrong Ruby version (which, before these
changes, might happen if they switch to a branch using a different Ruby
version and forget to run `rvm use` or exit the current folder and enter
it again) because they will get an error when trying to do so.
Second, people using services like Heroku no longer need to modify the
Gemfile.
The disadvantage is that, now, every time we update the Ruby version, we
have to remember to run `bundle` so our `Gemfile.lock` gets the new
version.
[1] https://github.com/rubygems/rubygems/releases/tag/bundler-v2.4.19
We were following it about half of the time and we even added it to our
former `.mdlrc` file. However, for some reason, MDL doesn't detect this
rule when specified in the `.mdlrc` file, so we didn't notice we weren't
following it in many cases.
Now that we're using a style file to configure MDL, we can enable this
rule again and apply it, since now MDL correctly includes it in its
report.
Note that, in order to have some consistency, we're always writing
"Consul Democracy", instead of using capital letters sometimes (but not
always), like we did until now.
This rule is broken when we have ".,;::!?" in the headers.
We have removed the ones with ":" but kept the ones
with "?", so this rule will always warn in these cases.
This is the Ruby version CONSUL uses now. Thanks to that, we no longer
need to install an old version of libssl-dev for Ubuntu 18.04.
We could probably simplify the documentation using:
```bash
rbenv install `cat .ruby_version`
```
However, this would require downloading consul before installing Ruby,
which could be harder to document.
