[BUG] Add version bump instructions for OpenSearch Dashboards plugins

[abhinavGupta16]

What is the bug?
The version bump does not work fully for dashboard plugins. The .json files for example are not edited with the sed commands - https://github.com/opensearch-project/opensearch-plugins/blob/main/META.md#increment-version-in-plugins

For example - https://github.com/opensearch-project/alerting-dashboards-plugin/blob/main/opensearch_dashboards.json https://github.com/opensearch-project/observability/blob/main/dashboards-observability/package.json needs to be updated when the version is bumped.

How can one reproduce the bug?
Execute the https://github.com/opensearch-project/opensearch-plugins/blob/main/META.md#increment-version-in-plugins for dashboard plugins

What is the expected behavior?
All version is bumped correctly in all the required files

[dblock]

These instructions were only for OpenSearch plugins, not OpenSearch Dashboards :) I should have made that clearer. Renaming this issue to support OSD plugins.