fix(flapping) start flapping on !OK state

[UrBnW]

Hi,

Description

it's possible for flapping algorithm to flag hosts and services as starting to flap when they switch from a non-OK to OK state.
Which, from a user point of view, is rather strange, as a FLAPPINGSTART notification will be sent, with a OK state.
Would make more sense to receive a FLAPPINGSTART notification with a non-OK state.
Let's then make a host or service starting to flap only when it switches to a non-OK state.
This gives it a very last chance not to be flagged as flapping, avoiding as such unneeded notifications.

Type of change

• Patch fixing an issue (non-breaking change)
• New functionality (non-breaking change)
• Breaking change (patch or feature) that might cause side effects breaking part of the Software
• Updating documentation (missing information, typo...)

Target serie

• 19.10.x
• 20.04.x
• 20.10.x
• 21.04.x
• 21.10.x (master)

How this pull request can be tested ?

Enable flapping detection, make a host or service to flap, and be sure it is flagged as flapping only when it switches to a non-OK state.

Many thanks 👍

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SonarQube Quality Gate:

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[omercier]

Hi,
Thanks a lot for your contribution!
This PR will be processed by our dev team for our 21.10 release.
Regards,
Olivier

[sonarqube-decoration]

SonarQube Quality Gate:

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[rem31]

this pr is fixed by it #552

[UrBnW]

Hi @rem31, really good news, perfect, many thanks 👍