[roll] Roll fuchsia [moniker] Rename PartialRelativeMoniker to RelativeMoniker

`PartialRelativeMoniker` (the moniker representation that does not
include instance ids) is renamed to `RelativeMoniker`.

This CL is a rename only and follows the conventions of
`AbsoluteMoniker`.

Original-Bug: 87407
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/639049
Original-Revision: 5ce72e2be1ef0783074f45d9b8a8910ed0fa3a42
GitOrigin-RevId: c22550ccd89364178569ceec57b6239d0a4f5ca7
Change-Id: Iedf167256eb5dbbd81338149ac6b7715de644be8
diff --git a/stem b/stem
index cc217d5..c5a206a 100644
--- a/stem
+++ b/stem
@@ -10,7 +10,7 @@
              githooks=""
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="f2ee9d34e6834244d840f0a4efb0380b4d39a9e6"/>
+             revision="5ce72e2be1ef0783074f45d9b8a8910ed0fa3a42"/>
   </projects>
   <hooks>
     <hook name="install-environment"