chore: Update docker to use node 18. (#151)

To fix this releaser error when trying to release react sdk 3.3.0:

```bash
stdout >> Installing typedoc
stderr >> npm WARN EBADENGINE Unsupported engine {
stderr >> npm WARN EBADENGINE   package: '@testing-library/[email protected]',
stderr >> npm WARN EBADENGINE   required: { node: '>=18' },
stderr >> npm WARN EBADENGINE   current: { node: 'v16.20.2', npm: '8.19.4' }
stderr >> npm WARN EBADENGINE }
stderr >> npm WARN EBADENGINE Unsupported engine {
stderr >> npm WARN EBADENGINE   package: '@testing-library/[email protected]',
stderr >> npm WARN EBADENGINE   required: { node: '>=18' },
stderr >> npm WARN EBADENGINE   current: { node: 'v16.20.2', npm: '8.19.4' }
stderr >> npm WARN EBADENGINE }
```

.ldrelease/config.yml

@@ -3,7 +3,7 @@ version: 2
 repo:
   public: react-client-sdk
   private: react-client-sdk-private
-  
+
 branches:
   - name: main
     description: 3.x
@@ -15,7 +15,7 @@ publications:
 
 jobs:
   - docker:
-      image: node:16-buster
+      image: node:18-buster
     template:
       name: npm
 
@@ -24,4 +24,4 @@ documentation:
   title: LaunchDarkly React SDK
 
 sdk:
-  displayName: "React"
+  displayName: 'React'