The headers of two of the code-snippets in the [Input section](https://angular.io/start#input)
of the "Getting Started" guide incorrectly referenced an non-existent
file path (`src/app/product-list/product-alerts.component.ts`).
This commit fixes the headers to show the correct file path
(`src/app/product-alerts/product-alerts.component.ts`).
Fixes#34320
PR Close#34321
Reference #33259
Removes figures elements as AIO is not typically using captions or image groups where figures would be necessary or appropriate
PR Close#33748
PR#28396 originally addressed an update via issue #23983 to make images more visible with a white background (implementation of gray "lightbox").
This PR implements those styles defined in PR#28396.
PR Close#33259
ajitsinghkaler
Stefanie Fluin
Judy Bogart
Geoff Bass
thanhpd
Mayur Barge
Kapunahele Wong
Eneko Nieto
Schlemmer
Lars Gyrup Brink Nielsen
jenniferfell