Increase the Windows OnFailureDelayDuration delay to 15s (#3657)

* Update Windows OnFailureDelayDuration to 15s.

This matches the value that endpoint uses and helps mitigate bugs where
agent unexpectedly restarts during a system shutdown.

* Add changelog.

* Update changelog/fragments/1698259940-Increase-wait-period-between-service-restarts-on-failure-to-15s-on-Windows.yaml

Co-authored-by: Paolo Chilà <[email protected]>

---------

Co-authored-by: Paolo Chilà <[email protected]>
(cherry picked from commit 910d17b)

changelog/fragments/1698259940-Increase-wait-period-between-service-restarts-on-failure-to-15s-on-Windows.yaml

@@ -0,0 +1,32 @@
+# Kind can be one of:
+# - breaking-change: a change to previously-documented behavior
+# - deprecation: functionality that is being removed in a later release
+# - bug-fix: fixes a problem in a previous version
+# - enhancement: extends functionality but does not break or fix existing behavior
+# - feature: new functionality
+# - known-issue: problems that we are aware of in a given version
+# - security: impacts on the security of a product or a user’s deployment.
+# - upgrade: important information for someone upgrading from a prior version
+# - other: does not fit into any of the other categories
+kind: bug-fix
+
+# Change summary; a 80ish characters long description of the change.
+summary: Increase wait period between service restarts on failure to 15s on Windows.
+
+# Long description; in case the summary is not enough to describe the change
+# this field accommodate a description without length limits.
+# NOTE: This field will be rendered only for breaking-change and known-issue kinds at the moment.
+description: This is the same value used by other Elastic windows services like endpoint-security.
+
+# Affected component; usually one of "elastic-agent", "fleet-server", "filebeat", "metricbeat", "auditbeat", "all", etc.
+component: "elastic-agent"
+
+# PR URL; optional; the PR number that added the changeset.
+# If not present is automatically filled by the tooling finding the PR where this changelog fragment has been added.
+# NOTE: the tooling supports backports, so it's able to fill the original PR number instead of the backport PR number.
+# Please provide it if you are adding a fragment for a different PR.
+#pr: https://github.com/owner/repo/1234
+
+# Issue URL; optional; the GitHub issue related to this changeset (either closes or is part of).
+# If not present is automatically filled by the tooling with the issue linked to the PR number.
+#issue: https://github.com/owner/repo/1234

internal/pkg/agent/install/svc.go

@@ -49,7 +49,7 @@ func newService(topPath string) (service.Service, error) {
 
 			// Windows setup restart on failure
 			"OnFailure":              "restart",
-			"OnFailureDelayDuration": "1s",
+			"OnFailureDelayDuration": "15s", // Matches the value used by endpoint-security.
 			"OnFailureResetPeriod":   10,
 		},
 	}