feat: added output schema docs (#1976)

Resolves: apify/apify-core#22480

This PR adds output schema docs. I have added a few examples, but there
is probably even more things that can be done with it. Will try to think
of more later.

---------

Co-authored-by: Michał Olender <92638966+TC-MO@users.noreply.github.com>

Author: gippy

package-lock.json

@@ -1,6 +1,6 @@
 ---
 title: Dataset schema specification
-sidebar_position: 3
+sidebar_position: 5
 description: Learn how to define and present your dataset schema in an user-friendly output UI.
 slug: /actors/development/actor-definition/dataset-schema
 sidebar_label: Dataset schema

sources/platform/actors/development/actor_definition/dataset_schema/index.md

@@ -2,7 +2,7 @@
 title: Dockerfile
 description: Learn about the available Docker images you can use as a base for your Apify Actors. Choose the right base image based on your Actor's requirements and the programming language you're using.
 slug: /actors/development/actor-definition/dockerfile
-sidebar_position: 4
+sidebar_position: 7
 ---
 
 **Learn about the available Docker images you can use as a base for your Apify Actors. Choose the right base image based on your Actor's requirements and the programming language you're using.**

sources/platform/actors/development/actor_definition/docker.md

@@ -1,6 +1,6 @@
 ---
 title: Actor input schema
-sidebar_position: 2
+sidebar_position: 3
 description: Learn how to define and validate a schema for your Actor's input with code examples. Provide an autogenerated input UI for your Actor's users.
 slug: /actors/development/actor-definition/input-schema
 ---

sources/platform/actors/development/actor_definition/input_schema/index.md

@@ -1,7 +1,7 @@
 ---
 title: Key-value store schema specification
 sidebar_label: Key-value store schema
-sidebar_position: 3
+sidebar_position: 6
 description: Learn how to define and present your key-value store schema to organize records into collections.
 slug: /actors/development/actor-definition/key-value-store-schema
 ---