ModuleEditorService.getModuleRoot() (#7816)

## Rationale
Make ModuleEditorService.getUpdatableResourcesRoot() return the path
used to resolve module resources. getModuleRoot() returns the module
source root (potentially parent of getUpdatableResourcesRoot())

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Author: labkey-matthewb

api/src/org/labkey/api/moduleeditor/api/ModuleEditorService.java

@@ -66,4 +66,11 @@ default File getFileForModuleResource(Module module, Path path)
             return null;
         return FileUtil.appendPath(resources, path);
     }
+
+    // used by ModuleResourceProvider@AllModuleResourcesRoot() (_webdav/@modules) which wants to soo
+    // the whole module source directory (e.g. when using SourcePath)
+    default File getModuleRoot(Module module, @Nullable List<String> messages)
+    {
+        return null;
+    }
 }