Update docs/building_and_running_tests.rst

Co-authored-by: Dai-Ni Hsieh <[email protected]>

docs/building_and_running_tests.rst

@@ -37,7 +37,7 @@ To run the tests, either run test binaries individually, or use `ctest` CMake te
 
 .. code-block:: bash
 
- # Run all tests
+  # Run all tests
   ctest
   # Run only Gpu specific tests
   ctest -R Gpu