Improve description of the release process (open-telemetry#1380)

* Improve description of the release process

Signed-off-by: Raphael Silva <rapphil@gmail.com>

* Update RELEASE.md

Co-authored-by: Tyler Benson <734411+tylerbenson@users.noreply.github.com>

---------

Signed-off-by: Raphael Silva <rapphil@gmail.com>
Co-authored-by: Tyler Benson <734411+tylerbenson@users.noreply.github.com>

Author: rapphil

RELEASE.md

@@ -4,4 +4,11 @@ The release process is almost entirely managed by [GitHub actions](https://githu
 
 1. Create a new tag for the layer to publish. For example, to create a new collector layer, the following command is used:
         `git tag layer-collector/0.0.8`
-2. Push the tag to [opentelemetry-lambda](https://github.com/open-telemetry/opentelemetry-lambda) repository to trigger the publish action.
+2. Push the tag to [opentelemetry-lambda](https://github.com/open-telemetry/opentelemetry-lambda) repository to trigger the publish action:
+        `git push origin tag layer-collector/0.0.8`
+3. Wait for the [release workflow](https://github.com/open-telemetry/opentelemetry-lambda/actions/workflows/release-layer-collector.yml) to finish.
+4. Create a release in https://github.com/open-telemetry/opentelemetry-lambda/releases/new
+    * Select a the newly pushed tag
+    * Select the corresponding previous release
+    * Click "Generate Release Notes"
+    * Adjust the release notes. Include the ARN, list of changes and diff with previous label.