Improve React, Vuejs and Angular integration pages

[tiny-ben-tran]

Will also resolve: TINY-13508

Site: Staging branch

Updated pages:

• React: Cloud, Self-host, Bundle, zip lazy-load, zip-bundle
• Angular: Cloud, Self-host, bundle, zip, zip-bundle
• Vuejs: Cloud, Self-hosted, bundle, zip

Changes:

• Removed duplicated and scattered guides on including premium plugins in integration pages
• Corrected the instructions on several pages
• Added a guide for bundling tinymce from .zip package in Angular

Pre-checks:

• Branch prefixed with feature/<version>/, hotfix/<version>/, staging/<version>/, or release/<version>/.
• modules/ROOT/nav.adoc has been updated (if applicable).
• Included a release note entry for any New product features.
• If this is a minor release, updated productminorversion in antora.yml and added new supported versions entry in modules/ROOT/partials/misc/supported-versions.adoc.

Review:

• Documentation Team Lead has reviewed

[tiny-james]

Just go and check that you are in the correct directory in the steps please.

[tiny-ben-tran]

Just go and check that you are in the correct directory in the steps, please.

@tiny-james, the command works as intended on macOS (iterm2 + zsh). Would it work differently on other OS(s)?

[kemister85]

LGTM, checked all staging builds to ensure partials are rendering- don't see any issues.