…ule` example app (#45706)

This commit updates the SystemJS for one of the example apps (the `upgrade-module` one) to include a resolution rule for the `tslib`. This is needed in case `tslib` is referenced from the framework code (for example in case of downleveling of some operators). This makes it consistent with other example app configs.

PR Close #45706

…diagnostics pages (#45634)

This commit aligns the layout of errors and extended diagnostics pages
more closely with other docs pages to ensure that the "Edit source"
button is displayed correctly even when the heading is too long to fit
on a single line. For error pages, in particular, this ensures that the
button is not obscured by the error video.

**Before:**
![error-pages before][1]

**After:**
![error-pages after][2]

[1]: https://user-images.githubusercontent.com/8604205/163408291-7aebd029-891c-4045-8fa2-a8e2b2b06dab.png
[2]: https://user-images.githubusercontent.com/8604205/163408296-40e6df8e-aadc-4a82-978a-ab4d902b6f6e.png

PR Close #45634

Add marker for noting that this check confirms we are running in a bazel environment.

PR Close #45728

PR Close #45764

replace the generic `*` selector used in the alert styling with
`p` (which is what gets generated from the markdown) as the styling adds
margins which are not always wanted

PR Close #45761

currently the aio home page presents a single h1 which is ignored by
assistive technologies since it has its display set none, so replace it
with a new h1 containing the main text of the page instead

PR Close #45740

convert the `div` groups in the aio home page
to proper `section`s with a valid heading/title

PR Close #45740

in the aio home page the sections' decorative images provide an alt
texts, which shouldn't actually be present
(see: https://www.w3.org/WAI/tutorials/images/decorative/), empty such
alt text for a better user experience

PR Close #45740