Replace obsolete finalizer with Java 9+ cleaner pattern
Replace obsolete finalizer with Java 9+ cleaner pattern

Helioviewer-Project/JHelioviewer-SWHV,Helioviewer-Project/JHelioviewer-SWHV,Helioviewer-Project/JHelioviewer-SWHV,Helioviewer-Project/JHelioviewer-SWHV,Helioviewer-Project/JHelioviewer-SWHV