Update example for prerelease versions to use semantic versioning syn…

…tax (#5361)

[Preview](https://docs-getdbt-com-git-dbeatty10-patch-2-dbt-labs.vercel.app/docs/build/packages#prerelease-versions)

## What are you changing in this pull request and why?

dbt-labs/hubcap#315 describes the difference
between prerelease versions in SemVer 2.0 ("semantic versioning") and
PEP 440 (used in the Python packaging ecosystem).

While the current example technically does work, it would more clearly
align with SemVer 2.0 if we update the example.

## Checklist
- [x] Review the [Content style
guide](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/content-style-guide.md)
so my content adheres to these guidelines.

---------

Co-authored-by: Mirna Wong <[email protected]>

website/docs/docs/build/packages.md

@@ -96,12 +96,12 @@ By default, `dbt deps` will not include prerelease versions when resolving packa
 - Explicitly specifying a prerelease version in your `version` criteria
 - Setting `install-prerelease` to `true`, and providing a compatible version range
 
-Both of the following configurations would successfully install `0.4.5a2` of `dbt_artifacts`:
+For example, both of the following configurations would successfully install `0.4.5-a2` for the [`dbt_artifacts` package](https://hub.getdbt.com/brooklyn-data/dbt_artifacts/latest/):
 
 ```yaml
 packages:
   - package: brooklyn-data/dbt_artifacts
-    version: 0.4.5a2
+    version: 0.4.5-a2
 ```
 
 ```yaml