Improvements to Deep Dive 2 and 3 content

[hatmarch]

This pull request represents enhancements to the 2. Elementary and 3. Intermediate sections of the tutorial. There are a lot of changes, but it can be easier to reason about the adoc changes looking at these changes rendered in antora here.

Changes at a high level:

1. Reorganizes Operator page to and adds more focus on CRDs (including updating example CRDs to v1 and kubectl explain)
2. Greatly expands exposition in the secrets section
3. Expands Jobs/Cron Jobs and cleans
4. Adds new watch to Intermediate section
5. Additional partials, examples, and consistency when referring to example files
6. Adds annotations to some shell commands and examples
7. Updates to (candidate) course-ui 0.1.12
8. Adds VS Code .devcontainer support and updates README for usage instructions thereof (devcontainer can also be used for tutorial walkthrough)

[hatmarch]

@lordofthejars (and @blues-man)> Please see additional changes that we discussed as outcome of the code review we did last week which includes:

• Updating to official rh-scholars course-ui v0.1.12 (with additional supplemental UI changes to get previous UI to match this version)
• Updating pod watch output in taints and affinity to match the watch
• Update StatefulSet section to correct errors and better demonstrate headless services

As always you can preview what my proposed changes look like when they are rendered here: