Getting segmentation fault error when creating PVC automatically

[BuddhiWathsala]

Description:
When creating PVC automatically, if the user did not specify the storage class name operator gives segmentation fault issue like below.

E0829 17:39:49.811061       1 runtime.go:69] Observed a panic: "invalid memory address or nil pointer dereference" (runtime error: invalid memory address or nil pointer dereference)
src/github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/runtime/runtime.go:76
src/github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/runtime/runtime.go:65
src/github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/runtime/runtime.go:51
/usr/local/bin/go/src/runtime/panic.go:522
/usr/local/bin/go/src/runtime/panic.go:82
/usr/local/bin/go/src/runtime/signal_unix.go:390
src/github.com/siddhi-io/siddhi-operator/pkg/controller/siddhiprocess/deploymanager/application.go:111
src/github.com/siddhi-io/siddhi-operator/pkg/controller/siddhiprocess/siddhicontroller/siddhicontroller.go:138
src/github.com/siddhi-io/siddhi-operator/pkg/controller/siddhiprocess/siddhiprocess_controller.go:249
src/github.com/siddhi-io/siddhi-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:215
src/github.com/siddhi-io/siddhi-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:158
src/github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/wait/wait.go:133
src/github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/wait/wait.go:134
src/github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/wait/wait.go:88
/usr/local/bin/go/src/runtime/asm_amd64.s:1337
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=0x8 pc=0x10192b3]

goroutine 351 [running]:
github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/runtime.HandleCrash(0x0, 0x0, 0x0)
	src/github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/runtime/runtime.go:58 +0x105
panic(0x127dda0, 0x21c4b20)
	/usr/local/bin/go/src/runtime/panic.go:522 +0x1b5
github.com/siddhi-io/siddhi-operator/pkg/controller/siddhiprocess/deploymanager.(*DeployManager).Deploy(0xc0009e7928, 0xc000a9ca89, 0x7, 0xc000d24440, 0x13)
	src/github.com/siddhi-io/siddhi-operator/pkg/controller/siddhiprocess/deploymanager/application.go:116 +0x1f43
github.com/siddhi-io/siddhi-operator/pkg/controller/siddhiprocess/siddhicontroller.(*SiddhiController).CreateArtifacts(0xc0009e7bc0, 0xc000317110, 0x2, 0x2)
	src/github.com/siddhi-io/siddhi-operator/pkg/controller/siddhiprocess/siddhicontroller/siddhicontroller.go:138 +0x324
github.com/siddhi-io/siddhi-operator/pkg/controller/siddhiprocess.(*ReconcileSiddhiProcess).Reconcile(0xc0004acf00, 0xc0005444c8, 0x7, 0xc0005da920, 0x11, 0x21d8c80, 0x8, 0x200, 0x40)
	src/github.com/siddhi-io/siddhi-operator/pkg/controller/siddhiprocess/siddhiprocess_controller.go:249 +0x87d
github.com/siddhi-io/siddhi-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem(0xc00029c5a0, 0x0)
	src/github.com/siddhi-io/siddhi-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:215 +0x1cc
github.com/siddhi-io/siddhi-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func1()
	src/github.com/siddhi-io/siddhi-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:158 +0x36
github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/wait.JitterUntil.func1(0xc000482410)
	src/github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/wait/wait.go:133 +0x54
github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/wait.JitterUntil(0xc000482410, 0x3b9aca00, 0x0, 0x1, 0xc000772480)
	src/github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/wait/wait.go:134 +0xf8
github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/wait.Until(0xc000482410, 0x3b9aca00, 0xc000772480)
	src/github.com/siddhi-io/siddhi-operator/vendor/k8s.io/apimachinery/pkg/util/wait/wait.go:88 +0x4d
created by github.com/siddhi-io/siddhi-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start
	src/github.com/siddhi-io/siddhi-operator/vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:157 +0x311

Suggested Labels:
Type fix

Affected Product Version:
0.2.0-m2

Steps to reproduce:

• Create a stateful distributed app without PVC spec's storage class.