[7.x] Fixed alerting health check behavior when alerting cannot find its health task in Task Manager. (#99564)

[YulNaumenko]

Backports the following commits to 7.x:

• Fixed alerting health check behavior when alerting cannot find its health task in Task Manager. (Fixed alerting health check behavior when alerting cannot find its health task in Task Manager. #99564)

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 36e7b27
• Storybooks Preview

Metrics [docs]

Unknown metric groups

References to deprecated APIs

id	before	after	diff
canvas	29	25	-4
crossClusterReplication	8	6	-2
fleet	4	2	-2
globalSearch	4	2	-2
indexManagement	12	7	-5
infra	5	3	-2
licensing	18	15	-3
monitoring	109	56	-53
total			-73

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream