Add DLL and PDB to Java gitignore

These files are commonly found when using Windows and/or VSCode and should not generally be checked in by default.  They are typically large and cause upload problems.

Java.gitignore

@@ -22,3 +22,7 @@
 # virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
 hs_err_pid*
 replay_pid*
+
+# Microsoft/VSCode files
+*.dll
+*.pdb