[roll] Roll fuchsia [bazel_sdk] Drop references to "Core" in tests README

Similar to https://fxrev.dev/1233186. Also make minor corrections about
implicit targets.

Replace references to the deprecated "core" product (no relation to the
Core IDK/SDK) with "minimal".

Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1237305
Original-Revision: 88d2f67d64483037e06d221cb61bdce9650c0697
GitOrigin-RevId: c4f25a7862fb0d1d4ad0f19cc9401e1e630d27ca
Change-Id: Iaa22ff90d1e25c2621e6fae4e59ddf5c4b65d20e
diff --git a/stem b/stem
index 2ba43cc..ae98e3c 100644
--- a/stem
+++ b/stem
@@ -11,7 +11,7 @@
              githooks="integration/git-hooks"
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="6c3054bcb4564852d1aa16404f6c9836d18cb29e"/>
+             revision="88d2f67d64483037e06d221cb61bdce9650c0697"/>
   </projects>
   <hooks>
     <hook name="install-environment"