[docs] Fix 301 links (@alexfauquette) (#42700)

Co-authored-by: Alexandre Fauquette <45398769+alexfauquette@users.noreply.github.com>

docs/pages/blog/mui-x-end-v6-features.md

@@ -146,7 +146,7 @@ Most notably:
   - New UI for column management
   - Pivoting for the [Premium](/x/react-data-grid/#premium-plan) version
 
-We'll continue to expand our portfolio of Charts, including [Heatmap](/x/react-charts/heat-map/), [Funnel](/x/react-charts/funnel/), and [Gantt](/x/react-charts/gantt/); and explore virtualization and other advanced use cases for the Tree View component.
+We'll continue to expand our portfolio of Charts, including [Heatmap](/x/react-charts/heatmap/), [Funnel](/x/react-charts/funnel/), and [Gantt](/x/react-charts/gantt/); and explore virtualization and other advanced use cases for the Tree View component.
 
 We encourage you to upvote issues on GitHub to help us prioritize.
 Your input directly influences our development schedule, so don't hesitate to let us know what matters most to you!

docs/pages/blog/mui-x-mid-v6-features.md

@@ -112,7 +112,7 @@ Check out the video below, highlighting some of our Charts:
 
 As we progress toward the stable version, we're committed to enhancing the overall experience for developers and users, so your feedback is fundamental!
 
-We will also steadily expand our portfolio with new chart types such as [Heatmap](https://mui.com/x/react-charts/heat-map/), [Funnel](https://mui.com/x/react-charts/funnel/), [Gantt](https://mui.com/x/react-charts/gantt/), and more.
+We will also steadily expand our portfolio with new chart types such as [Heatmap](https://mui.com/x/react-charts/heatmap/), [Funnel](https://mui.com/x/react-charts/funnel/), [Gantt](https://mui.com/x/react-charts/gantt/), and more.
 If there's a specific chart visualization you'd like us to prioritize, we encourage you to upvote the respective [issue on GitHub](https://github.com/mui/mui-x/issues?q=is%3Aissue+is%3Aopen+label%3A%22component%3A+charts%22+label%3A%22waiting+for+%F0%9F%91%8D%22).
 Your input can directly influence our development schedule, so don't hesitate to let us know what matters most to you!
 

docs/src/components/pricing/PricingTable.tsx

@@ -581,8 +581,8 @@ const rowHeaders: Record<string, React.ReactNode> = {
   'charts/pie': <ColumnHead label="Pie chart" href="/x/react-charts/pie/" />,
   'charts/sparkline': <ColumnHead label="Sparkline" href="/x/react-charts/sparkline/" />,
   'charts/gauge': <ColumnHead label="Gauge" href="/x/react-charts/gauge/" />,
-  'charts/treemap': <ColumnHead label="Treemap" href="/x/react-charts/tree-map/" />,
-  'charts/heatmap': <ColumnHead label="Heatmap" href="/x/react-charts/heat-map/" />,
+  'charts/treemap': <ColumnHead label="Treemap" href="/x/react-charts/treemap/" />,
+  'charts/heatmap': <ColumnHead label="Heatmap" href="/x/react-charts/heatmap/" />,
   'charts/radar': <ColumnHead label="Radar" href="/x/react-charts/radar/" />,
   'charts/funnel': <ColumnHead label="Funnel" href="/x/react-charts/funnel/" />,
   'charts/sankey': <ColumnHead label="Sankey" href="/x/react-charts/sankey/" />,