Fix CI profile to let profile group control phase on prerelease site (#1938)

Follow-up to #1932. Now that prerelease-subdomain is defined in
_quarto-prerelease-docs.yml rather than the phase profiles, the
profile group order correctly controls which phase is active on the
prerelease site. The explicit prerelease profile activation is no
longer needed and prevents RC branding from showing on
prerelease.quarto.org during RC phase.

(cherry picked from commit a34fdb6)

Author: cderv

.github/workflows/preview.yml

@@ -103,7 +103,7 @@ jobs:
       - name: Render 
         uses: quarto-dev/quarto-actions/render@v2
         env:
-          QUARTO_PROFILE: ${{ steps.prerelease-docs-check.outputs.is_prerelease_docs == 'true' && 'prerelease,prerelease-docs' || '' }}
+          QUARTO_PROFILE: ${{ steps.prerelease-docs-check.outputs.is_prerelease_docs == 'true' && 'prerelease-docs' || '' }}
 
       - name: Deploy Preview to Netlify as preview
         id: netlify-deploy

.github/workflows/publish.yml

@@ -47,7 +47,7 @@ jobs:
       - name: Render 
         uses: quarto-dev/quarto-actions/render@v2
         env:
-          QUARTO_PROFILE: ${{ (inputs.prerelease || (contains(fromJSON('["push", "workflow_dispatch"]'), github.event_name) && github.ref == 'refs/heads/prerelease')) && 'prerelease,prerelease-docs' || '' }}
+          QUARTO_PROFILE: ${{ (inputs.prerelease || (contains(fromJSON('["push", "workflow_dispatch"]'), github.event_name) && github.ref == 'refs/heads/prerelease')) && 'prerelease-docs' || '' }}
 
       - name: Publish release website
         # Only do this step if