docs: update docs for new features

docs/development/plugin-triggers.md

@@ -1345,8 +1345,28 @@ APP="$1"
 haproxy-build-config "$APP"
 ```
 
+### `post-release-builder`
+
+> Warning: Image mutation in this trigger may result in an invalid run state, and is heavily discouraged.
+
+- Description: Invokes a command after the build process is complete.
+- Invoked by: builder plugins
+- Arguments: `$BUILDER_TYPE $APP $IMAGE`
+- Example:
+
+```shell
+#!/usr/bin/env bash
+
+set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
+source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
+BUILDER_TYPE="$1"; APP="$2"; IMAGE=$3
+
+# TODO
+```
+
 ### `post-release-buildpack`
 
+> Warning: Deprecated, please use `docker-args-process-build` instead
 > Warning: Image mutation in this trigger may result in an invalid run state, and is heavily discouraged.
 
 - Description: Allows you to run commands after environment variables are set for the release step of the deploy. Only applies to apps using buildpacks.
@@ -1366,6 +1386,8 @@ APP="$1"; IMAGE_TAG="$2"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
 
 ### `post-release-pack`
 
+> Warning: Deprecated, please use `docker-args-process-build` instead
+
 > Warning: The pack plugin trigger apis are under development and may change
 > between minor releases until the 1.0 release.
 
@@ -1388,6 +1410,8 @@ APP="$1"; IMAGE_TAG="$2"; IMAGE=$(get_app_image_name $APP $IMAGE_TAG)
 
 ### `post-release-dockerfile`
 
+> Warning: Deprecated, please use `docker-args-process-build` instead
+
 > Warning: Image mutation in this trigger may result in an invalid run state, and is heavily discouraged.
 
 - Description: Allows you to run commands after environment variables are set for the release step of the deploy. Only applies to apps using a dockerfile.