Upgrading antora to 3.2.0-alpha.12

Author: ryanjbaxter

docs/package.json

@@ -1,10 +1,10 @@
 {
-     "dependencies": {
-         "antora": "3.2.0-alpha.11",
-         "@antora/atlas-extension": "1.0.0-alpha.5",
-         "@antora/collector-extension": "1.0.3",
-         "@asciidoctor/tabs": "1.0.0-beta.6",
-         "@springio/antora-extensions": "1.14.11",
-         "@springio/asciidoctor-extensions": "1.0.0-alpha.18"
-     }
- }
+  "dependencies": {
+    "antora": "3.2.0-alpha.12",
+    "@antora/atlas-extension": "1.0.0-alpha.5",
+    "@antora/collector-extension": "1.0.3",
+    "@asciidoctor/tabs": "1.0.0-beta.6",
+    "@springio/antora-extensions": "1.14.11",
+    "@springio/asciidoctor-extensions": "1.0.0-alpha.18"
+  }
+}