doc: deprecation of core script tasks (#462)

content/docs/15.migrations/core-script-tasks.md

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+---
+title: Deprecation of core Script tasks
+---
+
+Previously, there was scripting tasks inside the core plugin (the plugin that offers core task and is always included inside any Kestra distribution). Since the introduction of the new [Script tasks](https://kestra.io/docs/developer-guide/scripts) in dedicated plugins, the old core scripting tasks have been deprecated and moved out of the core plugin.
+
+If you use one of these tasks, you should migrate to the new one that offers improved scripting capabilities and runs by default in a separate Docker container.
+
+If you still want to use one of the old tasks and you don't use one of our `*-full` Docker images and manually install plugins, you must include the new plugin that now includes the old deprecated tasks.
+
+Here is the list of the old tasks with their new location and the replacement tasks:
+
+- The [Bash](https://kestra.io/plugins/plugin-script-shell/tasks/io.kestra.core.tasks.scripts.bash) task is now located inside the `plugin-script-shell` plugin and replaced by the Shell [Commands](https://kestra.io/plugins/plugin-script-shell/tasks/io.kestra.plugin.scripts.shell.commands) and [Script](https://kestra.io/plugins/plugin-script-shell/tasks/io.kestra.plugin.scripts.shell.script) tasks.
+- The [Node](https://kestra.io/plugins/plugin-script-node/tasks/io.kestra.core.tasks.script.node) task is now located inside the `plugin-script-node` plugin and replaced by the Node [Commands](https://kestra.io/plugins/plugin-script-node/tasks/io.kestra.plugin.scripts.node.commands) and [Script](https://kestra.io/plugins/plugin-script-node/tasks/io.kestra.plugin.scripts.node.script) tasks.
+- The [Python](https://kestra.io/plugins/plugin-script-python/tasks/io.kestra.core.tasks.scripts.python) task is now located inside the `plugin-script-python` plugin and replaced by the Python [Commands](https://kestra.io/plugins/plugin-script-python/tasks/io.kestra.plugin.scripts.python.commands) and [Script](https://kestra.io/plugins/plugin-script-python/tasks/io.kestra.plugin.scripts.python.script) tasks.