document `make quicktest`
I just learned that this exists so leaving a note for others.
@@ -189,6 +189,12 @@ The unit tests live with the code they test and can be run with:
make test
```
+You can also run a smaller set of unit tests that run quicker with:
+
+```shell
+make quicktest
+```
+
In case you see a linter error such as:
```shell
