[docs] Fix broken link to milestones (#43379)

Signed-off-by: Olivier Tassinari <olivier.tassinari@gmail.com>
Co-authored-by: Sycamore <71297412+samuelsycamore@users.noreply.github.com>

Author: oliviertassinari

docs/data/material/discover-more/roadmap/roadmap.md

@@ -24,8 +24,8 @@ We typically add umbrella issues to the project board after discussing them inte
 ### Milestones
 
 We also create milestones within the Material UI repository to keep track of larger cycles.
-Check it out to keep up with ongoing progress and see which issues have been picked up for the stable release.
+Check it out to keep up with ongoing changes and updates to the library.
 
-**[Visit the Material UI milestones page 👉](https://github.com/mui/material-ui/milestone/42)**
+**[Visit the Material UI milestones page 👉](https://github.com/mui/material-ui/milestones/)**
 
 <img src="/static/material-ui/roadmap/milestone.png" style="width: 814px;" alt="A screenshot from GitHub of the Material UI v6 milestone." width="1628" height="400" />