v2019.4: Release notes

Rendered here: https://em.pages.apertis.org/apertis-website/

Links are broken, so here are the pages involved:

• https://em.pages.apertis.org/apertis-website/release/v2019.4/releasenotes/
• https://em.pages.apertis.org/apertis-website/release/v2019.5/release_schedule/
• https://em.pages.apertis.org/apertis-website/policies/releases/

content/policies/releases.md

@@ -55,7 +55,7 @@ The next releases will be:
 
   - v2021dev3: [release schedule]( {{< ref "/release/v2021dev3/release_schedule.md" >}} )
   - v2020.2: [release schedule]( {{< ref "/release/v2020.2/release_schedule.md" >}} )
-  - v2019.5: [release schedule]( {{< ref "/release/v2019.4/release_schedule.md" >}} )
+  - v2019.5: [release schedule]( {{< ref "/release/v2019.5/release_schedule.md" >}} )
 
 For previous releases see: