Created by: tshinnic
Extending/elaborating of v3 docs for Popovers introduced confused names for doc example classes. Though v3 docs had similar confusion also.
/docs/assets/scss/_component-examples.scss defines class name
bd-example-popover. In file components/popover.md could be found
used class names bd-example-popover, bd-example-popover, and
bd-popover.
bd-popover was shown in page example code which is bad. Trying out
either .popover or .bd-example-popover did not produce useful
results, so this change simply deletes these references.
bd-example-popovers was 'corrected' to bd-example-popover in
the example "Live demo / Four directions". This added a background
which however looks out of place for that example, whereas the existing
use in structured example "Static demo" looks nice. Should the class
have been deleted instead in "Four directions"?
Also one spelling typo corrected.