fix crash in ViewImageFragment

[connyduck]

From Play console crash logs. Well, let's put another band aid on this code....

Exception java.lang.IllegalStateException:
  at androidx.fragment.app.Fragment.requireActivity (Fragment.java:1005)
  at com.keylesspalace.tusky.fragment.ViewImageFragment.getPhotoActionsListener (ViewImageFragment.java:59)
  at com.keylesspalace.tusky.fragment.ViewImageFragment.access$getPhotoActionsListener (ViewImageFragment.java:49)
  at com.keylesspalace.tusky.fragment.ViewImageFragment$onViewCreated$singleTapDetector$1.onSingleTapConfirmed (ViewImageFragment.kt:116)
  at android.view.GestureDetector$GestureHandler.handleMessage (GestureDetector.java:379)
  at android.os.Handler.dispatchMessage (Handler.java:106)
  at android.os.Looper.loopOnce (Looper.java:230)
  at android.os.Looper.loop (Looper.java:319)
  at android.app.ActivityThread.main (ActivityThread.java:8919)
  at java.lang.reflect.Method.invoke
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:578)
  at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1103)