bug: Operator fails with SIGSEGV while trying to create datastreams service without SA key

[mvgorbunov]

ydb-kubernetes-operator v0.5.22

Trying to create datastreams service without IAM SA key (just enable service in database specification)

spec:
  configuration: ""
  storageEndpoint: ""
  domain: dev
  resources:
    containerResources:
      limits:
        memory: 16Gi
      requests:
        cpu: 8
        memory: 16Gi
    storageUnits:
      - count: 1
        unitKind: ssd
  image:
    tag: "24.1.18-stream-nb-1.2"
    pullSecret: ydb-cr-puller
  nodes: 3
  datastreams:
    enabled: true

Operator gets crashed in reconcile loop:

2024-08-09T16:07:08Z	INFO	Observed a panic in reconciler: runtime error: invalid memory address or nil pointer dereference	{"controller": "database", "controllerGroup": "ydb.tech", "controllerKind": "Database", "Database": {"name":"stunder-test","namespace":"ydb-dev"}, "namespace": "ydb-dev", "name": "stunder-test", "reconcileID": "90537b9a-d16f-428e-933b-f0c3171a0db2"}
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
	panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x18c48d8]

goroutine 645 [running]:
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Reconcile.func1()
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.14.1/pkg/internal/controller/controller.go:119 +0x1fa
panic({0x1b33ce0, 0x2fe20b0})
	/usr/local/go/src/runtime/panic.go:884 +0x213
github.com/ydb-platform/ydb-kubernetes-operator/internal/resources.(*DatabaseStatefulSetBuilder).buildDatastreamsIAMServiceAccountKeyVolume(...)
	/workspace/internal/resources/database_statefulset.go:380
github.com/ydb-platform/ydb-kubernetes-operator/internal/resources.(*DatabaseStatefulSetBuilder).buildVolumes(0xc00cc41620)
	/workspace/internal/resources/database_statefulset.go:186 +0xd38
github.com/ydb-platform/ydb-kubernetes-operator/internal/resources.(*DatabaseStatefulSetBuilder).buildPodTemplateSpec(_)
	/workspace/internal/resources/database_statefulset.go:106 +0x85
github.com/ydb-platform/ydb-kubernetes-operator/internal/resources.(*DatabaseStatefulSetBuilder).Build(0xc00cc41620, {0x20f7200?, 0xc00c89ea00})
	/workspace/internal/resources/database_statefulset.go:63 +0x245
github.com/ydb-platform/ydb-kubernetes-operator/internal/controllers/database.(*Reconciler).handleResourcesSync.func1()
	/workspace/internal/controllers/database/sync.go:394 +0x5e
github.com/ydb-platform/ydb-kubernetes-operator/internal/resources.mutate(0xc00c89ea00?, {{0xc000e8c1c0?, 0x20e9188?}, {0xc000e8c190?, 0x20f7200?}}, {0x20f7200, 0xc00c89ea00})
	/workspace/internal/resources/resource.go:92 +0x55
github.com/ydb-platform/ydb-kubernetes-operator/internal/resources.CreateOrUpdateOrMaybeIgnore({0x20dd160, 0xc00cbc7290}, {0x20e9188, 0xc0003828a0}, {0x20f7200?, 0xc00c89ea00}, 0x0?, 0xc0007f5a68)
	/workspace/internal/resources/resource.go:165 +0x10a
github.com/ydb-platform/ydb-kubernetes-operator/internal/controllers/database.(*Reconciler).handleResourcesSync(0xc00095eb90, {0x20dd160, 0xc00cbc7290}, 0xc00cbbf690)
	/workspace/internal/controllers/database/sync.go:391 +0x2e5
github.com/ydb-platform/ydb-kubernetes-operator/internal/controllers/database.(*Reconciler).Sync(0x0?, {0x20dd160, 0xc00cbc7290}, 0x0?)
	/workspace/internal/controllers/database/sync.go:46 +0xf6
github.com/ydb-platform/ydb-kubernetes-operator/internal/controllers/database.(*Reconciler).Reconcile(0xc00095eb90, {0x20dd160, 0xc00cbc7290}, {{{0xc00133b406?, 0x0?}, {0xc00133b410?, 0x40de67?}}})
	/workspace/internal/controllers/database/controller.go:74 +0x214
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Reconcile(0x20dd160?, {0x20dd160?, 0xc00cbc7290?}, {{{0xc00133b406?, 0x1a836c0?}, {0xc00133b410?, 0x40f926?}}})
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.14.1/pkg/internal/controller/controller.go:122 +0xc8
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).reconcileHandler(0xc000319040, {0x20dd0b8, 0xc00095eaf0}, {0x1bcc7c0?, 0xc0003901a0?})
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.14.1/pkg/internal/controller/controller.go:323 +0x377
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem(0xc000319040, {0x20dd0b8, 0xc00095eaf0})
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.14.1/pkg/internal/controller/controller.go:274 +0x1d9
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2.2()
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.14.1/pkg/internal/controller/controller.go:235 +0x85
created by sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.14.1/pkg/internal/controller/controller.go:231 +0x587