Renames .platform.template.yaml for non-starter templates

[gilzow]

Closes #886 .

Renames the following templates' .platform.template.yaml file to .platform.experiment.template.yaml to designate their status as an example:

• Akeneo
• aspnet-core
• backdrop
• elastic-apm
• jenkins
• jetty
• lisp
• mattermost
• meilisearch
• micronaut
• microprofile-helidon
• mcrioprofile-kumuluzee
• microprofile-openliberty
• microprofile-payara
• microprofile-thorntail
• microprofile-tomee
• microprofile-wildfly
• nextcloud
• pelican
• pimcore
• probot
• quarkus
• rails
• sculpin
• spring-boot-gradle-mysql
• spring-boot-maven-mysql
• spring-kotlin
• spring-mvc-maven
• tomcat
• typo3
• typo3-v11
• xwiki

Renames the following templates' .platform.template.yaml files to .platform.demo.template.yaml to designate their status as a demo:

• drupal9-multisite
• eleventy-strapi
• gatsby-drupal
• gatsby-strapi
• gatsby-wordpress
• hugo
• nextjs-drupal
• nextjs-wordpress

Renames the following templates' .platform.template.yaml files to .platform.archived.template.yaml to designate their status as being archived:

• golang
• php
• python3
• python3-uwsgi
• strapi

Renames the following templates' .platform.template.yaml files to .platform.example.template.yaml to designate their status as being an example:

• nodejs