[analyzer] Prevent triplicate warnings for `sarif-html` (#158112)
When `-analyzer-output=sarif-html` is specified, the analyzer was
reporting each warning to the console three times. This is because the
code to create the diagnostic consumers for `sarif-html` was calling the
code for `sarif` and `html` separately, each of which also creates its
own console text consumer. Then the `sarif-html` code itself created a
third.
The fix is to factor out the creation of the SARIF and HTML consumers
from the text consumers, so `sarif-html` just calls the code to create
the SARIF and HTML consumers without the text consumers.
The same fix applies for `plist-html`.
I've updated one of the SARIF tests to specify `sarif-html`. This test
would fail in the regular `-verify` validation due to the triplicated
warnings, but now passes with my fix.
Fixes #158103
rdar://160383710