docs: add the new option for run configuration opt-out to the documentation

Author: ARau87

docs/configuration/overview.mdx

@@ -170,6 +170,19 @@ melos:
       executeInTerminal: false
 ```
 
+### generateAppRunConfigs
+
+Whether to generate the run configurations for flutter apps or not
+
+The default is `true`.
+
+```yaml
+melos:
+  ide:
+    intellij:
+      generateAppRunConfigs: false
+```
+
 ## scripts
 
 Define custom scripts that can be executed in the workspace via the