Move the b3-builder pin to the build that publishes doc assets

The release now uploads each plugin's README and CHANGELOG next to its .b3, and
the atom points the store at those files, so the notes on a plugin's store page
are the ones that shipped with the version being offered.

Author: unlucio

.github/workflows/pr-build.yml

@@ -37,7 +37,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - uses: Bespok3d/b3-builder@ff6ad98482c57c3966af1c1f7c8aefdf8be8c812  # main @ 2026-07-26
+      - uses: Bespok3d/b3-builder@06a36c4f6d487892d2a784945cd40359d80cf72c  # main @ 2026-07-31
         with:
           unit: repo
           bake: 'true'

.github/workflows/release.yml

@@ -29,7 +29,7 @@ jobs:
         with:
           fetch-depth: 0   # full history so the index.json push can rebase on a concurrent update
 
-      - uses: Bespok3d/b3-builder@ff6ad98482c57c3966af1c1f7c8aefdf8be8c812  # main @ 2026-07-26
+      - uses: Bespok3d/b3-builder@06a36c4f6d487892d2a784945cd40359d80cf72c  # main @ 2026-07-31
         with:
           unit: repo
           # Per-repo Actions secret today (GitHub Free cannot org-secret private repos); becomes ONE org