util: fix bug in health checker (backport #5272)

[mergify]

Describe what this PR does

This commit fixes a bug in health checker that
caused shared checker to get keyed with volumeID+volumepath instead of just volumeID and the other way around
for non-shared checkers.

unit test runs:

rakshithr4@fedora:~/Workspace/github.com/ceph/ceph-csi$ /usr/local/go/bin/go test -timeout 30s -tags ceph_preview -run ^TestTwoNonSharedChecker$ githu
b.com/ceph/ceph-csi/internal/health-checker -v
=== RUN   TestTwoNonSharedChecker
=== PAUSE TestTwoNonSharedChecker
=== CONT  TestTwoNonSharedChecker
    manager_test.go:99: start the first checker
    manager_test.go:105: check health for first path, should be healthy
    manager_test.go:111: check health for second path, should error out since checker is not started
    manager_test.go:113: 
                Error Trace:    /home/rakshithr4/Workspace/github.com/ceph/ceph-csi/internal/health-checker/manager_test.go:113
                Error:          An error is expected but got nil.
                Test:           TestTwoNonSharedChecker
    manager_test.go:115: start the second checker
    manager_test.go:121: check health, should be healthy
    manager_test.go:127: stop the first checker
    manager_test.go:130: check health of second path, should still be healthy
    manager_test.go:136: stop the second checker
--- FAIL: TestTwoNonSharedChecker (0.00s)
FAIL
FAIL    github.com/ceph/ceph-csi/internal/health-checker        0.005s
FAIL
rakshithr4@fedora:~/Workspace/github.com/ceph/ceph-csi$ git diff
diff --git a/internal/health-checker/manager.go b/internal/health-checker/manager.go
index ed78ec6fa..6a08e6b3d 100644
--- a/internal/health-checker/manager.go
+++ b/internal/health-checker/manager.go
@@ -137,7 +137,8 @@ func (hcm *healthCheckManager) startStatChecker(volumeID, path string, shared bo
 // are key'd by theit volumeID+path.
 func (hcm *healthCheckManager) startChecker(cc ConditionChecker, volumeID, path string, shared bool) error {
        key := volumeID
-       if shared {
+       if !shared {
+               // if it is non-shared checker, try to use the path as well.
                key = fallbackKey(volumeID, path)
        }
 
diff --git a/internal/health-checker/manager_test.go b/internal/health-checker/manager_test.go
rakshithr4@fedora:~/Workspace/github.com/ceph/ceph-csi$ /usr/local/go/bin/go test -timeout 30s -tags ceph_preview -run ^TestTwoNonSharedChecker$ github.com/ceph/ceph-csi/internal/health-checker -v
=== RUN   TestTwoNonSharedChecker
=== PAUSE TestTwoNonSharedChecker
=== CONT  TestTwoNonSharedChecker
    manager_test.go:99: start the first checker
    manager_test.go:105: check health for first path, should be healthy
    manager_test.go:111: check health for second path, should error out since checker is not started
    manager_test.go:115: start the second checker
    manager_test.go:121: check health, should be healthy
    manager_test.go:127: stop the first checker
    manager_test.go:130: check health of second path, should still be healthy
    manager_test.go:136: stop the second checker
--- PASS: TestTwoNonSharedChecker (0.00s)
PASS
ok      github.com/ceph/ceph-csi/internal/health-checker        0.005s

Checklist:

• Commit Message Formatting: Commit titles and messages follow
  guidelines in the developer
  guide.
• Reviewed the developer guide on Submitting a Pull
  Request
• Pending release
  notes
  updated with breaking and/or notable changes for the next major release.
• Documentation has been updated, if necessary.
• Unit tests have been added, if necessary.
• Integration tests have been added, if necessary.

---

Show available bot commands

These commands are normally not required, but in case of issues, leave any of
the following bot commands in an otherwise empty comment in this PR:

• /retest ci/centos/<job-name>: retest the <job-name> after unrelated
  failure (please report the failure too!)

---

This is an automatic backport of pull request #5272 done by [Mergify](https://mergify.com).

[ceph-csi-bot]

/test ci/centos/upgrade-tests-cephfs

[ceph-csi-bot]

/test ci/centos/k8s-e2e-external-storage/1.30

[ceph-csi-bot]

/test ci/centos/k8s-e2e-external-storage/1.32

[ceph-csi-bot]

/test ci/centos/upgrade-tests-rbd

[ceph-csi-bot]

/test ci/centos/mini-e2e-helm/k8s-1.30

[ceph-csi-bot]

/test ci/centos/mini-e2e-helm/k8s-1.32

[ceph-csi-bot]

/test ci/centos/k8s-e2e-external-storage/1.31

[ceph-csi-bot]

/test ci/centos/mini-e2e/k8s-1.30

[ceph-csi-bot]

/test ci/centos/mini-e2e/k8s-1.32

[ceph-csi-bot]

/test ci/centos/mini-e2e-helm/k8s-1.31

[ceph-csi-bot]

/test ci/centos/mini-e2e/k8s-1.31

[black-dragon74]

LGTM, thank you!