Remove katacoda plumbing

katacoda has been inoperable for a long time.  There is no suitable
alternative platform.

Signed-off-by: Aidan Delaney <[email protected]>

Makefile

@@ -170,22 +170,8 @@ tools-tidy:
 	cd tools; go mod tidy
 
 .PHONY: prepare-for-pr
-prepare-for-pr: check-links test tools-tidy katacoda
+prepare-for-pr: check-links test tools-tidy
 	@echo "========"
 	@echo "It looks good! :)"
 	@echo "Make sure to commit all changes!"
 	@echo "========"
-
-.PHONY: katacoda
-katacoda:
-	@echo "========"
-	@echo "Generating Katacoda docs..."
-	@go run katacoda/main.go
-	@echo "All done!"
-	@echo "========"
-
-.PHONY: check-katacoda
-check-katacoda: katacoda
-	@echo "Checking if Katacoda docs are up-to-date..."
-	@git diff --quiet HEAD -- katacoda/scenarios || ( echo "Katacoda docs are not up-to-date! Please run 'make katacoda' and commit the katacoda/scenarios folder" && exit 1)
-	@echo "All katacoda docs are up-to-date"

content/docs/app-developer-guide/_index.md

@@ -5,8 +5,6 @@ include_summaries=true
 expand=true
 +++
 
-{{< katacoda-button href="https://katacoda.com/buildpacks/scenarios/app-developer-guide" color="green" >}} Learn on Katacoda {{</>}}
-
 ## Prerequisites
 
 A lot of the examples used within this guide will require the following: 

content/docs/app-developer-guide/build-an-app.md

@@ -62,12 +62,6 @@ docker run --rm -p 8080:8080 sample-app
 The app should now be running and accessible via [localhost:8080](http://localhost:8080).
 <!--+end+-->
 
-<!--+ `
-Now open your favorite browser and point it to port "8080" of your host and take a minute to enjoy the view.
-
-On Katacoda you can do this by [clicking here](https://[[HOST_SUBDOMAIN]]-8080-[[KATACODA_HOST]].environments.katacoda.com)
-` +-->
-
 ## What about ARM apps?
 
 Linux ARM image builds are now supported!

content/docs/app-journey.md

@@ -7,15 +7,13 @@ getting-started=true
 ## Pack for the journey
 
 In this tutorial, we'll explain how to use `pack` and **buildpacks** to create a runnable app image from source code.
-<!--+if false+-->
-{{< katacoda-button href="https://katacoda.com/buildpacks/scenarios/app-journey" color="green" >}} Learn on Katacoda {{</>}}
 
 In order to run the build process in an isolated fashion, `pack` uses **Docker**. That means you'll need to make sure you have both `docker` and `pack` installed:
 
 {{< download-button href="https://store.docker.com/search?type=edition&offering=community" color="blue" >}} Install Docker {{</>}}
 
 {{< download-button href="/docs/install-pack" color="pink" >}} Install pack {{</>}}
-<!--+end+-->
+
 > **NOTE:** `pack` is only one implementation of the [Cloud Native Buildpacks Platform Specification][cnb-platform-spec]. Additionally, not all Cloud Native Buildpacks Platforms require Docker.
 
 [cnb-platform-spec]: https://github.com/buildpacks/spec/blob/main/platform.md
@@ -86,14 +84,8 @@ To test out your new app image locally, you can run it with Docker:
 docker run --rm -p 8080:8080 myapp
 ```
 <!--+- "{{execute}}"+-->
-<!--+- if false+-->
 Now hit [`localhost:8080`](http://localhost:8080) in your favorite browser and take a minute to enjoy the view.
-<!--+- end+-->
-<!--+ `
-Now open your favorite browser and point it to port "8080" of your host and take a minute to enjoy the view.
 
-On Katacoda you can do this by [clicking here](https://[[HOST_SUBDOMAIN]]-8080-[[KATACODA_HOST]].environments.katacoda.com)
-` +-->
 
 ### Take your image to the skies
 
@@ -107,9 +99,7 @@ deploying your new image to your favorite cloud!
 
 Windows image builds are now supported!
 
-<!--+- if false+-->
 <a href="/docs/app-developer-guide/build-a-windows-app" class="button bg-blue">Windows build guide</a>
-<!--+end+-->
 
 [builder]: /docs/concepts/components/builder/
 [buildpack]: /docs/concepts/components/buildpack/