Add preview env (#262)

* Add preview env

* Update docs-preview.yml

* Update docs-preview.yml

* Use reusable workflows

* Use reusable workflows

* Change version qualifier to main

Author: reakaleek

.github/workflows/docs-cleanup.yml

@@ -0,0 +1,14 @@
+name: docs
+
+on:
+  pull_request_target:
+    types:
+      - closed
+
+jobs:
+  docs-preview:
+    uses: elastic/docs-builder/.github/workflows/preview-cleanup.yml@main
+    permissions:
+      contents: read
+      id-token: write
+      deployments: write

.github/workflows/docs-preview.yml

@@ -0,0 +1,25 @@
+name: docs
+
+on:
+  pull_request:
+    types:
+      - synchronize
+      - opened
+      - reopened
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: ${{ github.ref != 'refs/heads/main' }}
+
+jobs:
+  docs-preview:
+    uses: elastic/docs-builder/.github/workflows/preview.yml@main
+    permissions:
+      contents: read
+      id-token: write
+      deployments: write
+    with:
+      strict: false