ARROW-9167: [Website] Keep /docs/c_glib/index.html

Closes apache#65 from kou/glib-keep-index and squashes the following commits:

d28fe18 <Sutou Kouhei> ARROW-9167:  Keep /docs/c_glib/index.html

Authored-by: Sutou Kouhei <kou@clear-code.com>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>

Author: kou

.github/workflows/deploy.yml

@@ -44,7 +44,7 @@ jobs:
             github.repository == 'apache/arrow-site'
       - name: Configure for GitHub Pages on master
         run: |
-          owner=$(jq .repository.owner.login ${GITHUB_EVENT_PATH})
+          owner=$(jq --raw-output .repository.owner.login ${GITHUB_EVENT_PATH})
           repository=$(jq .repository.name ${GITHUB_EVENT_PATH})
           echo "BASE_URL=/${repository}" >> ../env.sh
           echo "ORIGIN=${owner}/${repository}" >> ../env.sh
@@ -92,6 +92,10 @@ jobs:
             --exclude '/docs/' \
             ../build/ \
             ./
+          rsync \
+            -a \
+            ../build/docs/ \
+            docs/
           if [ "$(git status --porcelain)" != "" ]; then
             # There are changes to the built site
             git add --all

_docs/c_glib/index.md

@@ -32,5 +32,7 @@ Apache Arrow GLib supports [GObject Introspection][gobject-introspection]. It me
 
   * [Apache Arrow GLib](arrow-glib/)
   * [Apache Parquet GLib](parquet-glib/)
+  * [Gandiva GLib](gandiva-glib/)
+  * [Plasma GLib](plasma-glib/)
 
 [gobject-introspection]: https://wiki.gnome.org/action/show/Projects/GObjectIntrospection