pub fn set_exact_versions(&mut self, exact_versions: bool) -> &mut Self {
        self.exact_versions = exact_versions;
        self
    }
If set to true, outputs exact versions in package version fields.

By default, Hakari outputs the loosest possible version requirement that matches the
specified package. This is generally appropriate  if the `Cargo.lock` file isn't checked in,
and there's no automated process keeping the dependencies up-to-date.

In some cases one may wish to output the exact versions selected instead. For example:
* The `Cargo.lock` file is checked in and all developers have matching lockfiles.
* A tool like [Dependabot](https://dependabot.com/) is configured to update `Cargo.toml`
files to their latest versions.

## Note

If set to true, and the `Cargo.lock` file isn't checked in, Hakari's output will vary based
on the repository it is run in. Most of the time this isn't desirable.
tools/hakari/src/toml_out.rs