Add roadmap links for "Source locations"

RationaleMCP/0031/ReadMe.md

@@ -73,7 +73,7 @@ These are subtopics that are considered necessary to resolve for a first version
 - [x] Figure out what to do with synchronous features. [Design](https://github.com/modelica/ModelicaSpecification/blob/MCP/0031%2Bsynchronous/RationaleMCP/0031/differences.md#clock-partitions), [PR with discussion](https://github.com/modelica/ModelicaSpecification/pull/3240)
 - [x] Event handling semantics is preserved as in Modelica.
 - [ ] Get rid of `when initial()` and `when`-equations inside `if` and `for`. [Design](https://github.com/modelica/ModelicaSpecification/blob/MCP/0031%2Bsimplify-when/RationaleMCP/0031/differences.md#when-equations), [PR with discussion](https://github.com/modelica/ModelicaSpecification/pull/3258)
-- [ ] Source locations pointing back to the original Modelica code.
+- [ ] Source locations pointing back to the original Modelica code. [Design](https://github.com/modelica/ModelicaSpecification/blob/MCP/0031%2Bsource-locations/RationaleMCP/0031/source-locations.md), [PR with discussion](https://github.com/modelica/ModelicaSpecification/pull/3295)
 - [ ] Settle the name (currently _Flat Modelica_), considering that scalarization isn't mandatory. [Design](https://github.com/modelica/ModelicaSpecification/blob/MCP/0031%2Bname-of-the-game/RationaleMCP/0031/name-of-the-game.md), [PR with discussion](https://github.com/modelica/ModelicaSpecification/pull/3224)
 
 ### Flat Modelica 0.1+…1.0 (future MCPs)