SoC-2024: clarify distinction of first two projects

We have two projects related to migrating of unit tests. Clarify the difference between them clearly.

Author: sivaraam

SoC-2024-Ideas.md

@@ -30,7 +30,11 @@ framework.
 
 Our Outreachy intern ported some of the unit tests.
 
-See:
+**Note**: Owing to additional care needed to convert
+reftable unit tests in `t0032-reftable-unittest.sh`,
+it is covered as a separate project below.
+So, this project solely focuses on unit tests _other than_
+the reftable ones.
 
 - this discussion <https://lore.kernel.org/git/[email protected]/>
 -<https://lore.kernel.org/git/[email protected]/>
@@ -49,7 +53,7 @@ Possible mentors:
 
 ### Convert reftable unit tests to use the unit testing framework
 
-The "reftable" unit tests in "t0032-reftable-unittest.sh"
+The "reftable" unit tests in `t0032-reftable-unittest.sh`
 predate the unit testing framework that was recently
 introduced into Git. These tests should be converted to use
 the new framework.