Fix bogus indentation in RDF spec

CONTRIBUTING.md

@@ -135,6 +135,15 @@ This only needs to be run once after cloning the repository. After that, the tes
 $ make test
 ```
 
+If you are making a change to the documentation/specification, you should also
+check how your changes are rendered, by running
+
+```sh
+$ make serve
+```
+
+and opening `http://127.0.0.1:8000/sssom/` with your browser.
+
 Furthermore, any change to the LinkML model should also be tested against SSSOM-Py. To do so:
 
 1. In the current `sssom` repository, build the Python files derived from the LinkML:

src/docs/spec-formats-rdf.md

@@ -27,10 +27,10 @@ A metadata slot on any given SSSOM object (such as a `Mapping` or a
 
 - the subject is the resource representing the SSSOM object;
 - the predicate is either:
-  - the property indicated by the `URI` field in the LinkML description of the
-    slot, if such a field is present;
-  - or a property constructed by concatenating the `https://w3id.org/sssom/`
-    namespace and the name of the slot;
+    - the property indicated by the `URI` field in the LinkML description of
+      the slot, if such a field is present;
+    - or a property constructed by concatenating the `https://w3id.org/sssom/`
+      namespace and the name of the slot;
 - the object is the value of the slot.
 
 ### Representation of slot values