Removing folders verbiage from CONVENTIONS.md

We are removing the folders naming requirements since we are moving to one plugin per repo opensearch-project/opensearch-build#2188

Signed-off-by: Monica Kugler <monicank@amazon.com>

CONVENTIONS.md

@@ -8,9 +8,6 @@
   - [Artifacts](#artifacts)
     - [OpenSearch Plugins](#opensearch-plugins-2)
     - [OpenSearch Dashboards Plugins](#opensearch-dashboards-plugins)
-  - [Folders](#folders)
-    - [OpenSearch Plugins](#opensearch-plugins-3)
-    - [OpenSearch Dashboard Plugins](#opensearch-dashboard-plugins-2)
   - [Classes](#classes)
   - [Settings](#settings)
   - [APIs](#apis)
@@ -81,18 +78,6 @@ For example, [dashboards-notebooks/opensearch_dashboards.json](https://github.co
 
 - Artifacts are of the `<package name>-<version>` format, e.g. `notebooks-dashboards-1.0.0.0-beta1.zip`.
 
-### Folders
-
-#### OpenSearch Plugins
-
-- Always use kebab-case.
-- Include full plugin name, e.g. `plugins/opensearch-knn`.
-
-#### OpenSearch Dashboard Plugins
-
-- Always use kebab-case.
-- Include full plugin name, e.g. `plugins/notebooks-dashboards`. The change to automatically convert folders to kebab-case is still pending, see [OpenSearch-Dashboards#322](https://github.com/opensearch-project/OpenSearch-Dashboards/issues/322).
-
 ### Classes
 
 - Lowercase namespaces, e.g. `org.opensearch.jobscheduler`.