docs: use concrete example versions with labels for clarity

Signed-off-by: Rishav <bansalrishav047@gmail.com>

CONTRIBUTING.md

@@ -116,10 +116,11 @@ that we're already aware of. It is also worth asking on the Slack channels.
 
 ## Milestones
 
+## Milestones
+
 We use milestones to track progress of specific planned releases.
 
-For example, if the latest currently-released version is `X.Y.Z`, an issue/PR which pertains to a specific upcoming bugfix or feature release could fall into one of two different active milestones:
-`X.Y.(Z+1)` or `X.(Y+1).0`.
+For example, if the latest currently-released version is `1.2.3`, an issue/PR which pertains to a specific upcoming bugfix or feature release could fall into one of two different active milestones: `1.2.4` (next patch) or `1.3.0` (next minor).
 
 Issues and PRs which are deemed backwards-incompatible may be added to the next major version
 discussion using the relevant version label (e.g. [label:v4.x](https://github.com/helm/helm/labels/v4.x)).