Ignore suppressed findings in scheduled alerts

[ElenaStroebele]

Current Behavior

The scheduled NEW_VULNERABILITY_SUMMARY and NEW_POLICY_VIOLATION_SUMMARY are always sent(depending on skipPublishIfUnchanged) even if all findings are suppressed. Suppressed Findings are always included.

Proposed Behavior

If "ignoreSuppressed" is true (handled by a toggle in the scheduled alert menu), the suppressed findings are ignored and not mentioned in the final alert. If there are only suppressed findings, the alert is not sent at all. If "ignoreSuppressed" is true, there is a new template for the email and the summarizing content information, not including any mentioning of the number of suppressed findings and a note, explaining the suppressed findings are ignored. Following a Slack discussion. Further, changes required in the UI: new toggle beneath "Skip publish if unchanged" (see issue # 1374 in /frontend repo).

Detailed explanation of the combinations of skipPublishIfUnchanged and ignoreSuppressedFindings:

• skipPublishIfUnchanged = TRUE && ignoreSuppressedFindings == TRUE: notification only if there are new and unsuppressed findings
• skipPublishIfUnchanged = FALSE && ignoreSuppressedFindings == TRUE: notification always; notification is either empty or only includes unsuppressed findinds
• skipPublishIfUnchanged = TRUE && ignoreSuppressedFindings == FALSE: notification only if there are new findings, including both suppressed and unsuppressed ones
• skipPublishIfUnchanged = FALSE && ignoreSuppressedFindings == FALSE: notification always; notification is either empty or includes both suppressed and unsuppressed findings

Checklist

• [x] I have read and understand the contributing guidelines
• [x] I have checked the existing issues for whether this enhancement was already requested