Add excerpt field for posts

config/sync/field.field.node.post.field_excerpt.yml

@@ -0,0 +1,19 @@
+uuid: 909ad50d-08f1-4899-a43e-5f758c0f0759
+langcode: en
+status: true
+dependencies:
+  config:
+    - field.storage.node.field_excerpt
+    - node.type.post
+id: node.post.field_excerpt
+field_name: field_excerpt
+entity_type: node
+bundle: post
+label: Excerpt
+description: ''
+required: false
+translatable: false
+default_value: {  }
+default_value_callback: ''
+settings: {  }
+field_type: string_long